NERSCPowering Scientific Discovery Since 1974

2003 User Survey Results

Overall Satisfaction and Importance

SatisfactionAverage Score
Mostly Satisfied 5.5 - 6.4
Somewhat Satisfied 4.5 - 5.4
ImportanceAverage Score
Very Important 2.5 - 3
Somewhat Important 1.5 - 2.4
Significance of Change
significant increase
significant decrease
not significant

Overall Satisfaction with NERSC:

TopicNo. of ResponsesAverageStd. Dev.Change from 2002Change from 2001
Account Support Services 245 6.39 1.05 0.01 -0.04
Overall satisfaction with NERSC 298 6.37 0.88 0.05 0.12
Consulting Services 233 6.34 1.01 0.04 0.04
Network Connectivity 241 6.23 0.94 0.16 0.20
Available Computing Hardware 255 6.13 1.06 0.16 0.02
Mass Storage Facilities 207 6.12 1.10 0.08 0.07
HW management and configuration 210 6.07 1.07 -0.03 0.25
Available software 242 6.05 1.09 0.07 0.24
SW maintenance and configuration 213 6.04 1.20 -0.13 0.12
HPCF Website 213 6.00 1.10 -0.09 -0.18
Allocation Process 196 5.69 1.26 -0.15 -0.31
Training 94 5.04 1.26 0.05 0.12
Visualization Services 97 4.81 1.17 -0.02 0.30

Importance to Users:

TopicNo. of ResponsesAverageStd. Dev.Change from 2002Change from 2001
Overall satisfaction with NERSC 267 2.84 0.39 0.00 0.02
Available Computing Hardware 236 2.84 0.41 -0.05 0.03
Network Connectivity 223 2.75 0.47 -0.00 -0.07
Allocation Process 183 2.68 0.56 0.11 0.01
HW management and configuration 187 2.66 0.56 -0.05 0.04
Consulting Services 227 2.59 0.61 0.01 -0.05
Account Support Services 230 2.54 0.60 0.07 0.10
Mass Storage Facilities 190 2.53 0.62 0.02 0.05
SW maintenance and configuration 194 2.52 0.62 -0.02 -0.08
Available software 222 2.50 0.64 -0.03 -0.06
HPCF Website 197 2.39 0.64 -0.13 -0.10
Training 116 1.80 0.79 0.00 0.28
Visualization Services 125 1.60 0.75 -0.02 -0.11

Why do you compute at NERSC?

[Read all 229 responses ]

Many of the answers were along the lines of "to run my codes in order to get my science done". Users pointed out that they need powerful compute resources that they can't get elsewhere. Many users specifically mentioned large numbers of processors or parallel computing as a reason to compute at NERSC. Turnaround time (getting results fast) is very important. Data analysis, especially in the context of PDSF computing is also a common theme. One user even pointed out that the time is "free".

139 Need lots of compute power to do science (focus on compute resources)
32 Focus on data analysis / PDSF
31 NERSC is a well run center / provides good services:
20 Need lots of storage and compute power
10 Need large memory (and lots of storage and compute power)
8 Need to test / install / maintain software
3 Other


QuestionNo. of ResponsesAverageStd. Dev.Change from 2002Change from 2001
How satisfied are you with NERSC security? 261 6.37 1.09 NA NA

Has security gotten in the way of your work at NERSC?

No. of Responses
No 217 (90%)
Yes 23 (10%)

If yes, how?

[Read all 26 responses]

10 Access problems (ssh, secure ftp)
6 Password problems, Failed login attempts
3 HPSS access difficult
3 Grid, Distributed computing, Collaborative computing
3 It's inconvenient
1 Security is OK

How do you compare NERSC openness and access to your home site and others?

[Read all 146 responses]

49 (34%) Similar openness
41 (28%) NERSC's openness / security measures are good
23 (16%) NERSC is more open / more flexible
13 (9%) NERSC is less open / more restrictive; too secure / too complicated
2 (1%) Concerns about NERSC security
2 (1%) Home site is secure
1 (0.7%) NERSC is less secure
4 (3%) Other

Flexible Work Option at NERSC

Beginning in May, NERSC started participating in Berkeley Lab's Flexible Work Option (FWO) Pilot. FWO means some staff work 9 hours a day and are off one day every two weeks. NERSC always has on duty qualified staff for all areas.

Have you noticed any changes specifically due to the FWO participation?

No. of Responses
No 220
Yes 0

If so, describe your experience. 2 responses


Why do you compute at NERSC? 229 responses

Note: the responses have been broadly categorized by response category and also color-coded by topic. Individual responses have sometimes been split across several response categories (this is indicated by ...). The response categories are:

139 Need lots of compute power to do science (focus on compute resources)
32 Focus on data analysis / PDSF
31 NERSC is a well run center / provides good services:
20 Need lots of storage and compute power
10 Need large memory (and lots of storage and compute power)
8 Need to test / install / maintain software
3 Other

The color codes are:

  • Need powerful computing resources / good hardware management, good uptime
  • Focus on the number of processors / scaling
  • Focus on parallel computing
  • Good network connectivity
  • Focus on getting science done
  • Focus on data analysis
  • User support, good staff
  • Job scheduling / turnaround time
  • Can't get the research done on local systems / couldn't do the research without NERSC
  • Documentation
  • Software / user environment
  • The time is "free"


Need lots of compute power to do science (focus on compute resources): 139 responses

we need to test our program to see how well it scales up (up to 6000 cpu - if possible) since we need these kind of compute power to simulate the whole ecoli metabolism reactions in real life

The chief attraction is the sheer size of seaborg. Being able to run on 1024 or more processors allows our group to look at cutting-edge problems.

One of the very few sites where I can use several 1000 processors.

Large scale computation using 1000 PEs for days

NERSC is very important for my research because of the larger number of processors available for computations. Requesting 512 or more CPUs is very possible at NERSC.

I need access to large numbers of processors (> 512) to run my scientific computations

To have access to a large (larger than 200's) of PE system. This provides the compute power required for the calculations.

This is our only computer resource, and our research does need large scale parallel computer (> 64 processors)

Need to do parallel processing on a minimum of 16 processors

For production runs of Quantum Monte Carlo simulations on the SP-cluster, since it has 16 CPUs on each node.

Lots of processors!

Availability of large number of nodes on the SP.
Homogeneity of the cluster.

Because I can use a large number of nodes.

The total number of processors it has provides a necessary condition for our large scale computation.

I perform large scale mhd and pic simulations of magnetically confined plasmas for fusion applications and need a massively parallel computer to carry them out.

I need massively parallel computers to run particle simulations.

The main reason is the high speed of computing using parallel computers. It allows us to achieve the numerical accuracy needed for the beam-beam simulation at very high beam intensities.

Large parallel code and multinode computing for cosmological simulations. Mainly run several simulations in parallel to produce a large number of simulations fast.

Because there is a very fast parallel computer: seaborg.

The ability to perform massively parallel simulations

We need the cycles and can run more effectively on a massively parallel architecture.

... I use a sophisticated (and complicated) MPI+SMP fortran (and C, C++) program that computes the radiative properties of Supernova, Nova, White Dwarfs, and whole slew of other astrophysical objects. This code works very well on the IBM and parallelizes very well. I also have had a long (happy) history with IBM hardware. ...

available high-performance parallel computing

Staff on my project use NERSC to perform DFT calculations of defect properties in ceramics and to carry out Molecular Dynamics simulations of high-energy ion-solid interactions. NERSC provides the parallel platforms that are otherwise unavailable to my project.

I need the parallel computer facilities to run a chain of "consecutive codes" in an input-output structure. I also need to calculate a high number (up to 20,000) realizations of our modeled system to obtain good enough statistics.

My problems need a stable, large-scale parallel computer. NERSC is the best the system of which I am aware to which I am likely to be granted access.

Advanced electronic structure calculations are extremely demanding to be run on single CPUs. Seaborg offers an ideal platform for parallel computing.

Need for massively parallel computations

we can do large scale parallel computation work on nersc. For current particle acceleration experiment, simulation can help to design the experiment, and predict the experiment results. With the help of super computers and parallel algorithm, we can simulate the plasma acceleration experiment more accurate and faster.

NERSC is our only large scale parallel computer

Parallel computing using SP for high resolution numerical simulations of carbon dioxide disposal in geologic formations

Because it is the only place where I can perform my simulations in parallel processing

I need access to highly parallel computing resources.

Parallel computations, ...

Need lot of computing time for transport calculations. Huge time saving (trivial parallelization) using the computer farm (batch system).

Need massively parallel machines ...

My work focuses on object-oriented high performance computing. NERSC provides the hardware to test and run my code on a massively parallel computer.

Parallel computers

For fast and massively parallel calculations

I compute at NERSC as I need the parallel processing power of pdsf to run my physics simulations and analysis. It would take far too long to run on a single machine.

I have been using Alvarez for parallel processing of electron micrograph images

Groundwater simulations. Important because of the large computing resource.

I'm running time-demanding quantum chemistry calculations. These calculations would not be possible on a single UNIX machine.

In years 1997-98 I used Cray T3E to develop lattice quantum theory of scattering processes and performed extensive computations of scattering cross sections. These results, considered today as benchmark, wouldn't be possible without the NERSC support. Since 2001 I have been using IBM SP. My current research concerns parallel discrete-event simulations (PDES) for stochastic modeling of information-driven systems. This research opens a new interdisciplinary area between non-equilibrium statistical physics and computer science. It contributes to basic research in non-equilibrium surface growth and complex systems as well as being a pilot study that applies methods of surface science to performance studies of algorithms for PDES. The access to the NERSC computing facilities allowed me to perform large-scale simulations that wouldn't be possible otherwise. Currently, this study is in the publishing stage. I very much appreciate the opportunity of having access to the NERSC facilities. I hope to use IBM SP and visualization services in my future computational projects.

I compute at NERSC because adds more computing time for my calculations

IBM SP is the only machine available to me that can handle my simulations.

Need computing power

Because they give my boss computer time :)

large scale astrophysical simulations that cannot be run on a serial machine or a cluster with relatively few CPU's

Free and fast

Size of the system - enabling large calculations

I need two orders of magnitude more FPO's than is available to me from other computers (and reasonable turn-around time).

As an experimentalist in Surface Physics collaborating with a theorist, large supercell calculations are an important part of my work. Without the computer resources required to perform these calculations, many advances in the field of surface science (including some of our work) would not be possible.

NERSC is an essential resource for our large-scale atmospheric modeling under our DOE grant. NERSC provides the computing power needed for our work.

Heavy computer time simulations

I do Monte Carlo simulations related to the Relativistic Heavy Ion Collider. These are large scale simulations that require many machines and a lot of computer time to accumulate statistics.

The problem size and runtime are big that massively multiple machines such as the NERSC SP2 are needed for computations.

To allow large simulations of complex regimes to be analyzed quickly

Computing essential to research

One of two places nationally that has the power to do my problems (to which I have access).

Fastest computer I have ever used!

For large computation that my computer cannot handle

Need capability beyond single CPU desktops --- the ability to do >100-hour runs in less than a day can be very important.

NERSC is the major computing resource available to us. It provides much-needed computer power that would otherwise be unavailable.

Seaborg allows significant acceleration of our large scale simulations of atomic structures.

It is faster and more stable than other resources I can use.

I compute at NERSC because it saves me valuable time. It also allows me to run test simulations to see if there is anything wrong with my input files before running a complete simulation.

Large scale SPDE simulations.

I get simulations done much faster than in any other computing facilities, saving a lot of time.

NERSC has the most powerful computer hardware. This makes it possible to carry out the most demanding scientific computations.

The NERSC IBM 'seaborg' is the fastest and most efficient (turnaround time) machine available for my research. Without it, my scientific output would drop by a factor of 4.

The facilities and computer time are not available elsewhere

These SPs have the most cpus per node and show the best scalability among available machines. ...

Availability of large scale computing power that is not really available elsewhere!

it is faster than others

fast, large-scale calculations of excited state electronic structure - one-two orders of magnitude faster than desktop

Large resources make speedy work. ...

It is pretty much the only facility where I can do computations around. Besides, the computing speed is second to none. However, waiting time on queue seems to grow significantly, considering last year and this year.

I can perform larger simulations, with faster turnaround times, than elsewhere. ...

NERSC provides much needed processing time

the other computer resources that I usually use are too small for a lot of tasks

Perform large-scale fluid flow and head flow simulations which can not be done on other computers.

large amount of jobs submission.

Do the large scale problem

NERSC is the best supercomputer for civilian research.

This is the most powerful computer system I have access to.

supercomputing power

a lot of resources!

NERSC provides extremely fast, powerful computing services. ...

Computing at NERSC forms the core of my basic research. The simulations we run on the IBM-SP are indispensable to our entire programme.

Big codes need big machines, this is one of the few available to me.

It allowed for large computations leading to the design of the new detect (EMCal for ALICE experiment at LHC)

Fast computing, and possibility of running many jobs at once.

It's where our group is running large simulations to which I'm bound. Availability of SMP nodes is important.

I use NERSC IBM computer for large scale calculations, not amenable on the computer at NREL

I have a research group composed of 5 Ph. D. students, two post-doctoral associates, and several undergraduate students. Most of them have accounts at NERSC. It is very important for my research (purely computational) to have access to NERSC computers.

I run Quantum Monte Carlo jobs for electronic structure. NERSC is very important for me because it gives me access to an important amount of computer time, which is basic for my research

I am studying proteins with dft and molecular mechanics, I need to use many computers in order to get results.

NERSC runs the largest computing system for scientific research in the United States.

For me it is a very important tool to do my research. I use NERSC to make runnings of molecular dynamic simulations.

NERSC allows me to conduct massive calculations that would be impossible with my in-house facilities.

It provides the high end computing facilities that are essential to my research

NERSC has fast supercomputers ...

Running climate model for climate simulation needs supercomputer

Access to large SP computer.

Use seaborg to conduct computations for one of SciDAC projects.

I am working on my thesis and doing virtually all my calculations through NERSC.

The primary allocations for our project are seaborg

NERSC offers me unmatched computing resources. I simply cannot do my research without NERSC.

I am computing at NERSC because the scientific problem I am working on (computational nuclear structure theory related to DOE experimental programs) would take too much CPU time on my local LINUX workstation (about 3 weeks compared to 20 hours at the IBM-SP at NERSC). Therefore, being able to compute at NERSC is essential for my research productivity.

Need more CPU than I can get locally; run into inconvenient CPU time limits often.

access to fast computers

The only facility adequate for large Monte Carlo transport calculations

NERSC is the only large-scale computing facility that is generally available for fusion energy computation. As a computational physicist, these resources are critical for my group's work.

I do big simulations. DOE gives me a big allocation. Where else could I go? I am a computational physicist, so NERSC is vitally important to me. DOE and NERSC take good care of me.

we do climate modeling. In order to do the experiments to evaluate physical parameterizations on climate time scales and have them in a reasonable and useful time requires a computer of the scale of the SP. A local workstation would just take way too long to be useful and would not allow the number or different simulations that are required not the horizontal and vertical resolution required.

Without NERSC, I can't complete numerical calculations within reasonable times. In some cases, the calculations become impossible.

Multiprocessor simulation for SASE FEL Development.

Larger scale computations than I can do at home.

most powerful computing resources available to me

we have to run very large jobs beyond the local computing capability

We require for climate model studies top of the line HPC.

NERSC has fast computation facilities which is essential to my research.

Because NERSC can supply the computation power needed for my research.

I need run my code on SuperComputer

Very fast machine ...

Save some time to get the job done.

the powerful resource NERSC can provide is the most important reason, We can't do our research in our university machines.

I am working on Monte Carlo simulations, with some important modifications to try to do some new and valuable things.

Because I am doing my primary research using NERSC seaborg.

We perform molecular dynamics simulations of large protein molecules and protein complexes.

Running Quantumchemical Simulations for my PhD research

Ab initio and MD calculations.

I compute at NERSC because it allows me to do physics that would be impossible otherwise. NERSC resources are directly related to my competitiveness within my community.

I am doing on a SciDac Project to simulate the chemical reaction of spray combustion. As the reaction is very stiff, we have to use very fine grid and very short step step to perform the simulations. NERSC is very important to the successful completion of the project.

for my Ph.D. research

I use it for research in support of the Terascale Supernova Initiative, a DOE-funded project administered through the SciDAC program.

NERSC resources are essential for my research

Mathematica and Matlab calculations, some big protein structure calculations. I wish SAS was still on the new newton. also the control system toolbox for matlab isn't available. I find the system difficult to learn and use; for most big calculations it is easier to use my local linux cluster and just wait awhile for the calculations to finish. [math server user]

  Focus on data analysis / PDSF: 32 responses

Some STAR data only available at PDSF

KamLAND data analysis

work for the STAR experiment at BNL, doing analysis

STAR data Analysis

One of only two sites where our data is stored

It's important for the data analysis of my thesis project.

PDSF is the main analysis site for our experiment. HPSS is used as our main data archive system.

Component separation in astrophysical data; CMB power spectrum estimation from CMB data; Cleaning CMB data from systematic effects

We transfer data from Brookhaven National Lab to NERSC for star computing.

I use the PDSF system to work on STAR data. This is much easier than trying to work at BNL over the network.

data reduction and analysis for STAR experiment

This is for a practical reason. All the embedding data files I use are at pdsf

ATLAS grid

Data retrieval

As a member of STAR, I need to use pdsf for my analysis work

analyzing huge data sets of observations of the cosmic microwave sky

STAR computing

physics analysis

I use the CMIP data that is exclusively archived at NERSC HPSS

I am a member of the STAR collaboration and PDSF represents a major fraction of our computing resources.

All of our experiment's data is on HPSS/PDSF.

I am a member of the STAR Collaboration. The embedding jobs are run at NERSC

RHIC data analysis.

Data analysis and simulations for ultra-relativistic nuclear collisions, STAR & RHIC

availability of PDSF for massive data and simulation productions


To do US ATLAS Grid Computing. We (U. Oklahoma) are one of the 11 testbed sites, just like LBL is one.

Part of the data I use are located on nersc disk (and only there). I never had problems to do what I needed to do.

I am a member of STAR experiment at RHIC

Software development and analysis for the KamLAND experiment NERSC is our main computing resource and we couldn't do without it.

Research for STAR


  NERSC is a well run center / provides good services: 31 responses

I am involved primarily in capability computing. The NERSC facility provides an excellent balance of high performance networking to raw compute power which I am unable to find in most commodity cluster environments.

Simply without access to NERSC I could not complete most of my research projects. My group makes enormous use of NERSC and over the last 22 years we have come to rely on NERSC for access to parallel supercomputers, access to novel and useful algorithm packages (QD and SuperLU) and access to advice on tricky technical questions.

It is one of the best in the whole world; much better than NCSA.

We have performed some grand challenge climate model computations (High resolution climate modeling and Coupled carbon cycle and climate modeling) recently. These are unclassified work. NERSC has been one of the primary resources for these computations. When I need to perform computationally demanding climate model simulations, NERSC has provided the best solution for me.

NERSC provides a parallel platform with reasonable power per processor and a queuing structure that makes it possible for users who need an intermediate number of processors (64-128) to compute.

NERSC is by far the best computing service I have ever used. I've been at NPACI, NCSA (and way back in time to the Cornell Theory center). While these other places are fine, NERSC has always been on top of every thing. Consulting Services at NERSC contains the most thoughtful and responsive group of people around. I've used the consulting services to deal with software issues on several occasions and 100% satisfied (give those guys a raise!). ... And, most importantly, my work gets done at NERSC and done fast!

NERSC is a well maintained and powerful service that is essential for my research analysis. With our data volume, the HPSS system is a necessary tool. Processing our data with the PDSF batch system is reliable and simple.

... Also the long queue times available on Seaborg are really nice for long running big jobs, which you don't want to checkpoint and restart too often. Recently I also started using Escher for some post processing on large amounts of data produced on Seaborg. I was really pleased with the assistance of the consulting service in figuring out how to best transfer the data and for allowing me to use most of the disk space on Escher for an extended time.

... maintained STAR experiment software

availability of math libraries, powerful software, good consultants

Queue wait times seem reasonable (they are generally quite short) for all job sizes. The quick turnaround on jobs makes everything much easier, from development, through debugging, and onto production.

excellent queue response. all kinds of production job sizes in my experience start very quickly. queue time limits are very nice, in particular the 48 hour limit.

NERSC is one of the most user friendly and powerful centers in the country. Having computed or moved data through most of the other centers, I say this from experience. The support staff, particularly in mass storage, have been extremely helpful in setting up a data archive which has had a tremendous impact on my field (lattice gauge theory).

... Many resources are well documented, especially on the web, and very handy to use.

Less portability problems than on many other super-computers I use, predictable queueing policies

... Good support. Environment is maintained well and has very little downtime.

... SP machine is stable, and well-managed. Effort of getting time is well worth it.

... I have found NERSC resources very easy to learn how to use to get what I need to done and am very happy with it in general.

... Eric Hjort and Iwona Sakrejda are _extremely_ helpful and prompt. Super user support compared to Brookhaven/rcf.

... It is nice to get real-time answers.

NERSC computing tends to be stable and reliable.

... availability of math software (Matlab).

Consistent turn-around time. Availability of short, fast debug cycles. Consulting

NERSC has ... great support.

NERSC offers a flexible, significant, large scale computational facility. In short, we can do serious, cutting-edge research in a timely fashion at NERSC.

NERSC has excellent computing facilities, it is easy to use, and has been reliable.

I worked for a summer using Seaborg to run computational chemistry simulations. I enjoyed using the computational resources of NERSC. The account support people made it easy for me to get set-up and working quickly.

...with the necessary support.

Most of my simulations require a mainframe. NERSC is an excellent central computing facility, with first-rate support.

... The documentation on the website is excellent, and the support staff has been great at filling in any gaps and at clarifications.

... with STAR library loaded.

  Need lots of storage and compute power: 20 responses

The performance and storage resources are necessary for the research project.

Analyzing large datasets and performing large simulations not feasible on a desktop.

PDSF offers huge parallel cpu power, and there is easily accessible mass storage space (>100 GB) for users. ...

Massive computing for analyzing CDF data.

high performance computing and mass storage

Because of the computational resources and the available disc space.

I need to process lots of data fast.

I need the computing power made available by seaborg to do my research. The large amount of disk space also makes it possible for me to do more complicated analyses.

NERSC is our major source of high performance computing. HPSS at NERSC is the major backup system for our projects which are sometimes spread over many sites.

Lots of CPU; Disk space ...

Lots of compute power on PDSF, lots of storage on HPSS.

I'm in charge of data processing for the KamLAND experiment and NERSC is a vital resource in this endeavor. We're big users of th e batch queue and HPSS, two systems without which our job would be impossible.

CPU power and large scratch disks to cache data samples.

I use nersc to process data from HPSS and run any jobs that would take longer than 10 minutes on my computer here. ...

Availability of mass data storage and large number of computer nodes for running many jobs at once.

Our data sits there (STAR).
Closest batch job facility.

I perform all-electron fully relativistic Dirac-Fock calculations for the electronic structure of systems of superheavy elements with hundreds of electrons ( an example is Seaborgium Hexabromide molecular species with 316 electrons!). The formalism we developed in 1975 can handle such problems but the resulting gargantuan calculations require huge amounts of CPU even on the supercomputers. In addition disk storage of ~ 20-50 Gbytes may be needed for each calculation ( which is freed after the completion of the calculation,of course). Since experimental chemical ( and physical) information about the man-made superheavy elements is scarce due to their very short life ( ~ a few seconds at best) and production of ~ half a dozen atoms. Therefore atomic and molecular systems of these superheavy elements are ideal systems to be studied theoretically , and we can make predictions about their chemistry and physics. We have been studying the chemistry ( and physics) of the superheavy elements Rutherfordium ( atomic number Z=104) to the primordial superheavy elements E126 ekaplutonium ( Z=126) and their numerous compounds. The results have been mentioned in the various ERCAP applications and published in open literature and featured in Chemical and Engineering News as News of the Week ( see Dec 16,2002, issue of Chemical and Engineering News). Such calculations can only be performed at the state-of the art superb world-class supercomputing facility like NERSC and nowhere else! This is my motivation for using NERSC facility, which is sine quo non for my theoretical research in the prediction of the Chemistry of man-made superheavy transactinide elements with Z=104-126.

NERSC is the ideal facility for the computing I have been doing. I usually run jobs on 1-4 nodes of the SP, generating large output files. The connectivity between the SP and the HPSS is splendid and allows me to use these large files several times, which saves on computing time. My jobs have usually been going through the queue without much waiting. ...

The large storage resources of HPSS are critical to storing our terabytes of astronomical images and PDSF is similarly vital to processing all of that data. The resources to provide either on our own would be significant obstacles to our scientific research.

Fast computing facility with massive storage.

  Need large memory (and lots of storage and compute power): 10 responses

3d simulations need memory

We need a large memory and fast machine to do first-principles calculations and collaborative works with Dr. L. W. Wang at NERSC.

I use NERSC (Seaborg) for very large scale simulations, that is difficult to fit into memory on most other machines I have access to. ...

Thc computer is fast, and has large memory. The archive is very good. Our job needs all above properties.

Enough memory available for high level calculations

Our large scale simulation of accelerator structures requires huge amount of memory and CPUs. NERSC IBM SP2 provides the parallel runtime environment and suitable amount of memory and CPUs for our simulations.

Large simulations requiring more than 500 GB of RAM. NERSC is one of the only sites with this capability. Smaller simulations can be done elsewhere.

Because I am running jobs that are rather large (>10Gbytes) and computationally intensive, which makes it impossible to run them on a single machine.

It has a lot of nodes with a huge amount of memory. I could not solve my problems in a common PC cluster because of lack of memory.

Big jobs that require large memory and more CPU time.
To get fast turn around time.

  Need to install / test / maintain software: 8 responses

I have only used NERSC to do some routine maintenance on NetPIPE (

I am a staff and I do work on projects that require NERSC computing resources - HPSS/PDSF. I work however, mostly on Linux and Solaris workstations.

I work on domain decomposition methods for numerical PDE's. Parallel scalability is one of the main concerns in this area and it is very important for me to run experiments in many processors.

For testing the performance and scalability of programs intended to use for benchmarking on the IBM SP up to large number of processes.
to develop performance prediction methods
to develop system characteristics and numbers that describe the usage of a parallel system ( Peak Application Performance PAP, Reached Application Performance)

I use the NERSC computers to test the performance and scalability of numerical software.

To setup and validate atlas servers at CERN with offsite clients

I am developing software ( in Titanium language ) for serious PDE simulations.

CCSM software testing.

  Other: 3 responses

I do not do computing at NERSC, only use the mass storage facility

I use the NERSC in the frame of the CMIP project... I did not compute on the NERSC system, but only FTP to get the data. I find the procedure very complicated and not well documented on the information I was looking for. A good thing that I was able to contact the people there by phone and that they were very helpful.

I used to use Killeen, but I don't really use anything anymore.


If security has gotten in the way of your work at NERSC, how?

Access problems (ssh, secure ftp): 10 responses

I haven't had any problems so far. But I don't understand the need of the exclusive use of ssh protocol 2. I expect to have some problems with connections from both and from my PC at home. I will deal with it in October, when the transition v1-to-v2 occurs.

In the beginning we had to set up port forwarding in order to use CVS to check out our code on seaborg making it somewhat cumbersome. However this has changed and is not longer necessary, so this complaint has disappeared.

with the retirement of FTP, I had to look for and install new software to access my NERSC login, and to transfer files from my Mac to/from NERSC. This conversion process was quite painful for a while..

Because of a lot of security measures, tunneling through html and perl doesn't seem to be allowed, which one of my simulations programs needs.

complaints when I log in directly from a foreign dial-up connection when traveling. now I log in to a university computer first and then connect from there.

Sometimes I had troubles displaying graphics on my Mac even using SSH and MacX. I tested the same SSH+MacX combination else where from my computer and had no problems.

Encrypted communication.

It take me a long time to connect there and to get the data I needed... Sometime, it does not work, and I have no idea why... Sometime it does... and I do not know why...

Very frequently, I receive a message saying the host key has changed and there might be a "man-in-the-middle" attack. I ignore the message, but it worries me every time I see it.

Too many complicated procedures to set up connections to mainframes, to mass store, for file transfer, etc....

Password problems / failed login attempts: 6 responses

Unwanted login's (not successful) where detected.

expiring passwords

I think that in general the security at NERSC is fairly good, while not being overly draconian. I have just one serious complaint: The new (DOE?) directive to disallow shared accounts is giving us a serious headache in terms of how to do our data analysis. Typically, our data is reconstructed during a 1-2 month period, once every ~6months. We would like to share the responsibility of doing the reconstruction among a small group of people, rather than one individual. The granularity of group permissions is simply not adequate to achieve this task. A shared account would make it much easier for us. It is also not clear to us what the reason is for disallowing shared accounts. If it is accountability, then there are other ways of implementing something that would maintain a trail of who logged into the account at a given time.

I did not log in for 2 months and then I cannot change my password what was required. Problems!

My login to seaborg is disabled about 50% of the time, forced me to login and work from much of the time.

Minor Suggestion:
I'd like the number of times I'm allowed to mistype my password to increase from 3 to around 5-8. My passwords are random, and I'm a bad typist. I'm always afraid of being locked out due to mistyping or misremembering the password, although it's only happened once.

HPSS access difficult: 3 responses

The current access to HPSS from outside through ftp has severe limitations. One difficulty is when one wants to access HPSS from multiple systems sharing a common home file system, but independent data disks. The second deficiency is that ftp has no mechanism for copying directory trees from one system to another.

the initial setup for mass storage access was painful. It is however well documented and once setup works easily. I made the mistake of not setting it up prior to an important job. When I had the data I thought that with my account login I could just use mass storage. I started to sweat quite a bit when I realized that this didn't work. I was afraid the system might delete my data before I had a chance to transfer it to mass storage. It worked out OK in the end.

The HPSS password "keys" wasn't well documented on the web and caused me a few calls to the consultants. The lack of documentation may have been part of the security, though, so although it took me a bit of time, it was probably necessary.

Grid / distributed computing / collaborative computing issues: 3 responses

Hardly any distributed computing work can be done on networked workstations that try to access NERSC.

There are needs for group and role-based work that is not handled very well with just the unix uid/gid capabilities. There are some new developments for helping this type of work in grid software that will be helpful. I hope that NERSC could be more proactive in this regard.

Strict security and firewalls and the likes tend to get in the way of Grid computing, since used ports aren't always predictable, and we have to find ways around it. Luckily, that's usually possible, just takes some time.

It's inconvenient: 3 responses

A bit of inconvenience that's all

I am located in Munich, Germany. All security matters which require a phone call during the Pacific time zone working hours are difficult due to the 9 hour time difference.

Security enhancements usually require a little time and effort to understand and adjust to the new regime (typically a few hours to a day).

Other (security measures OK): 1 response

Security appears adequate without being a major obstacle.


How do you compare NERSC openness and access to your home site and others? 146 responses

Similar openness: 49 responses

Very similar.


Comparing with the, I'd say, they are both very secure. I haven't experienced any problems yet.




About the same

About the same.

The security is good. I don't really have anything other to compare it to besides the University's site. Comparatively, it's just as good, if not better.

I have seen no difference in the security measures; they seem equivalent to the other systems I work with.

No comments really. I access NERSC computers the same way I access all other computers with SSH.

It is comparable and in some ways more open than my home site. Other sites vary.

very similar

similar to LBNL

about the same

computer security and access at nersc seems on par with LBL's network ...


Roughly the same level.

About the same.

more or less equivalent, slightly better maybe

Security seems about the same as at most similar institutions.


It is comparable


I do not feel much difference as of the access.

similar or perhaps more secure


About the same.........


Nearly equal

Computer security at Berkeley is very tight. NERSC equals or exceeds their high standards.


About equally hard compared to my other large-scale computing on my university.

The same, I'm on-site.

No noticeable difference to me.

Similar to my home institution (LBL). ...



About the same.

Fermilab uses kerberos V. After the snags of the first few months of its implementation has provided a successful environment of operation. Access of the NERSC facilities allows for comparable freedom, but the problems with alvarez security where annoying (and we haven't had such a large scale problem at FNAL, although it might be luck)



comparable to our campus computing facility.


home site has comparable level of security

Very similar.

NERSC computer security is similar to my home site, both are quite reasonable.

About the same, as far as I can tell. I just do what the experts tell me to do.

Similar. NERSC security doesn't seem particularly intrusive, nor does it seem lax.

NERSC's openness / security measures are good: 41 responses

Very balanced: openness vs. security

Use of SSH provides good security while not making things too difficult, due to the wide availability of clients.

Seems secure, but I am not an expert.

The network is very fast and the access via ssh very convenient

it's fine

I use secure ssh, and had no trouble.

Very good

Well, I use ssh everywhere (if I could start my car with ssh I would!) I don't know what the rest of the people on campus are using. I have never had any problems getting info to and from NERSC. I think the level of security at NERSC it pretty good. ...


pretty good



The openness of NERSC is excellent.

excellent, I haven't noticed any problems since the access has been restricted to ssh only

I think it is good.

I've never had any problems in regards to security when using NERSC machines.

SSH seems to be the best system.

NERSC has easily usable yet secure facilities.


I think NERSC does a fine job of balancing security with ease of use and openness.

I am very satisfied with openness and access.

Not aware of any problem.

I think it quite secure (I wish I can say "very secure"....but I can't since I just use NERSC facilities less than 3 mos) ... but so far I think it's quite secure.

To my estimation, NERSC security is pretty tight, but necessary and not a barrier of my work.


NERSC computer security seems very reliable and efficient.

I think NERSC has taken a "common-sense" approach, which does not hamper productivity


Very good.

I do not really concern about the security problem. But I think nersc is good because I never lose my data, and I was asked to changed my password often.

i think that it is one of the best about the support, the security, the visualization, and the computational time.

NERSC has struck a good balance between security and usability in my opinion.

We are fully ssh so it is seamless security between my computer and NERSC. It seems like this should be the standard everywhere, so NERSC compares favorably.

NERSC is open without being sloppy. I think the security is effective without being intrusive.

It is not necessary to compare any computer facility with NERSC! If we had accessibility at a facility similar to NERSC, it would be not sensible to use NERSC! The very fact that thousands of scientists throughout the world have been using and still continue to use NERSC speaks for itself about the user-friendly atmosphere at NERSC without which nothing much can be achieved in scientific research by thousands of users of NERSC.

very good



well maintained and very good

Basically security is not an issue to me for now, so all the machine's security openness are enough for me.

I am for.

NERSC is more open / more flexible: 23 responses

It is much more flexible than Livermore's policy.

From discussions with my colleagues, NERSC has a security openness unique to DOE labs. Frankly that make NERSC computers "user friendly" and allows us to get our work done without undo extra work arounds. I think that openness is a crucial part of making NERSC a success. While I realize that security is important also.

I think NERSC computer security openness and access is better than what we have here.

Much more easily accessed than others I have experienced and have not found this to compromise security

NERSC computer security openness/access is probably a bit better than the security environment here at Yale Physics Department.

... with both being far superior to BNL's network, which is fraught with obstructions (closed ports, restricted gateways, etc), in ease of use, performance, and security.

Better than Rhic Computing Facility (Brookhaven)

better than RCF. its nice to be able to sftp to/from the current host, and not have to go through a gateway machine or dedicated sft machine.

NERSC is doing an excellent job when compared to other DOE unclassified computing facilities.


It's much simpler to access NERSC than comparable machines. The ssh access and other security features are totally transparent and do not cause any trouble for me or reduce convenience. I am very happy with the setup.

NERSC security is much less bothersome that security at other sites I'm familiar with.

For the responsible user, NERSC is a model of transparency from the security point of view. The other place I work intensively is the RHIC Computing Facility at Brookhaven, where security is obtrusive and in-your-face. It is apparent that NERSC is as secure, but with much less overhead for the user. Good work!

Access is much better as well as openness. The access to NERSC is straight forward and simple compared to other large computing sites I have used.

NERSC beats the RHIC computing facility hands down. RCF is fairly draconian in its approach to security and makes it complicated to connect and use the resources. I much prefer working at pdsf (NERSC).

I have had no problems with NERSC security. I greatly prefer computing at NERSC to computing on any of the platforms at LLNL because security at NERSC is much less troublesome.

The NERSC site is more open than some sites that I use. I can directly connect to seaborg using ssh and sftp, whereas at some sites the firewall limits the direction that such connections can be made.

NERSC is more open than my home site. We have experienced numerous security problems in the Astronomy department which has lead to severe security measures which negatively impact the use of our machines.

... It is pleasantly more open than other sites I have dealt with.

NERSC's security process is less intrusive than at most places I compute, but appears to be just as effective.


I work at LLNL. Our security is more rigorous and requires more effort by the users and the supporting staff.

It is better than my home site.

NERSC is more secure: 15 responses

more secure than other facilities I have used, but easily accessible

NERSC is far more secure.

NERSC is on the top of the security level list of the places I use.

NERSC is much more secure

NERSC is much more secure

It seems to be more secure than my home site.

NERSC is more secure.

NERSC seems to be the most secure computing site that I use.

It is more secure in NERSC computers.

The NERSC computer security is better than my home site.

It is very secure compared to my computer

Although NERSC is more secure than my home site (U of Maryland), the extra protection doesn't adversely affect the openness or access. I'm quite satisfied with the NERSC security and, in fact, wish my home site would be as conscientious.

It is more safe.

Tighter, but not restrictive.

It appears much more secure than our university site.

NERSC is less open / more restrictive / too secure / too complicated: 13 responses

it is kind of too secure

Comparing against the Rhic Computing Facility, they allow the use of shared accounts. It makes organizing the analysis of physics experiments much easier (people take reconstruction 'shift').

It's a little more awkward, but this is mostly because it is a remote site and not the configuration per se.

The necessity for different passwords/access to the system and mass storage is not obvious to me as the user and I have never seen that at another site.

OK but seem to have complicated multiple passwords when I was asked to update my user profile. Required phone call and was still unsuccessful so ignored request.

NERSC is more restrictive than average, not allowing ssh 1.0 (I think it is). This often means that I have to scp FROM seaborg TO local machines, and not opposite. No big deal, though.

A bit too complicated access.

Much more complicated...

I have experienced some problems depending on the node used during the access. For instance, was not accessible while was. I use a Window application called cygwin.

NERSC security seems a little more conservative, but it really is no problem at all. My work does not require high security, but the current system has worked very well for me.

U. Oklahoma has a less restrictive firewall (or rather, ACLs), and we have full control over which ports are opened if we have the need for it. Of course, it's not a National Lab, so we can get away with slightly less security.

Slightly tighter (than CERN) which allowed telnet and ftp until quite recently (and still has an insecure ftp service but you will probably never guess which machine it is on). ...

Too cumbersome to access.

Concerns about NERSC security: 2 responses

... However, a few times I have requested my password over the phone. At that level, I thought the guy on the other end didn't ask me enough questions. At least on one occasion (more than a year ago) I felt like any body could have called and (with a little "social engineering") obtained my password. But maybe these guys have caller id?

... As I've forgotten my password (from now on I will risk writing it down) it will be interesting to see how long it takes to get a new one. At CERN/opal/atlas I would do this for a known colleague in my next coffee break. At SLAC/Babar I think it took a week and I had to make phone calls at midnight Birmingham UK time.

Home site is secure: 2 responses

Well, my desktop runs linux, and I don't have any security problem, as I update regularly all available patches, and I feel more comfortable with my desktop in that any graphics and programs can possibly run without any security hassle.

Our home site is pretty safe so far, primarily because of the restricted access policies we have been implementing very consistently. Therefore, we do not see our system as a potential loophole for NERSC.

NERSC is less secure: 1 response

Homesite computers are not reachable except via hosts.allow, which is very restricted. Therefore homesite is more secure than NERSC.

Other: 4 responses

I am an LBNL employee, so I'm not familiar with the other sites.

Unclear on what this means

It is the only choice for us to have access to a highly parallel real production system. Our inhouse system has only 130 CPUs.

usually NERSC is less crowded


Flexible Work Option at NERSC

Beginning in May, NERSC started participating in Berkeley Lab's Flexible Work Option (FWO) Pilot. FWO means some staff work 9 hours a day and are off one day every two weeks. NERSC always has on duty qualified staff for all areas.

If you have noticed any changes specifically due to the FWO participation, describe your experience: 2 responses

The only problem I encountered was a consultant working at home (probably not FWO). Here the consultant re-routed calls to his home that had a block on caller-ID. This generated a confusing message that lead me to believe that I had the wrong number - it wasted some of my time.

I don't use seaborg on daily basis. But, there were couple times when I really needed to run something on it, it was down accidentally.