NERSCPowering Scientific Discovery Since 1974

2002 User Survey Results

Comments about NERSC

 

What does NERSC do well?   92 responses

49  

User support, good staff

42  

Well run center, good hardware (specific systems not specified)

16  

Documentation

13  

Job scheduling / batch throughput

10  

Seaborg

8  

HPSS / data storage

7  

PDSF

7  

Software / user environment

2  

Training

 

What should NERSC do differently?   66 responses

10  

Job Scheduling

7  

Allocations / accounting

7  

Software

7  

Documentation

7  

Provide more computing resources

6  

Provide better hardware

5  

Keep the PVP Cluster / maintain a PVP resource

5  

Training / new user services

4  

No need for change / no suggestions

3  

PDSF

3  

More outreach / collaborations

2  

More interactive services

2  

Networking

1  

HPSS

1  

No inode quotas

 

How does NERSC compare to other centers you have used?   62 responses

36  

NERSC is the best / very good / overall NERSC is better

11  

NERSC is the same as / mixed response

8  

No comparison made

7  

NERSC is less good


Notes:

  • Comments displayed in green are repeated in multiple categories.
  • Comments with ... have been split and only part of the response is displayed in a given category.

What does NERSC do well?   92 responses

User support, good staff:

High level of technical expertise!

... The staff is friendly, helpful and proactive in developing training on new hardware and making debugging and performance tools easier to use.

People at NERSC that I interact with are great! They take pride in their work.

your consultants are your best feature; ...

User Services are great. The people are extremely competent and dependable, and a pleasure to work with.

Technical and general consulting services are fantastic.

The overall job scheduling (load), user support, and documentation are the best in the world.

Support users and applications. Willingness to work with specific applications that need special access or help. Availability of support personel.

Your consultants and account folks have been very responsive, helpful, informative, and easy to work with.

NERSC's response to users needs and consulting are the best.

Provide information (as on web sites), accounts management, consulting.

Consulting, web-site, provision of a lot of good relevant information.

Support. Hardware availability.

Consulting and web resources.

Among the supercomputing facilities I tried until now, NERSC excells in most aspects. I am most satisfied with the overall stability of the system. This must come from the outstanding competence of the technicians.

Good response and professional service.

... Information services, training, account management, and consulting are all excellent.

Accuracy of information, platforms available and support.

Excellent user support, good hardware selection.

I really appreciate the job fron consult. They always did their best to help me to resolve my technique problems, especially at starting to use seaborg.

User support is great.

Usually can add users quickly, get problems resolved quickly. Seems very "customer oriented". ...

... Account support has also been very good. I also appreciate the seeming concern about security.

hardware management and consulting services

I only use PDSF and HPSS but am very happy with all aspects, uptime, disk volume, batch processing, expert help ....

1. Excellent User services and support. ...

Consulting and supporting services.

... consulting service ...

... After a few initial problems getting the code compiled and running (the support was very helpful in this) we haven't seen many problems. Our project seems to have been given an allocation outside of the usual procedure, as far as I understand. We also had some special requests for larger disk allocations, and I think a problem with the number of inodes which was limiting us. These things were resolved, and we were very impressed by your ability to make accomodations for these special requests.

The support we get from the PDSF staffer is superb. Keep up with the good work!

... account creation ...

Good consulting services.

NERSC user services have been very helpful. ...

Very good hardware and support.

NERSC functions amazingly well and seems to have a user-oriented focus that is very refreshing to deal with. My colleagues and I generally feel that we are not taking full advantage (due to time constraints) of all that NERSC has to offer.

... And the consultanting and help system is fantastic. Keep it up!

... Its consulting services are outstanding.

Consultant service is great.

... Good consulting support.

consulting and account support services excellent.

Web site, consulting, account queries

Human service is great.

I have always found consultants helpful. ...

... Account support

Consulting is generally good. NERSC seems to be better at not "fixing things not broken" than the previous LLNL management

User support and interaction.

Consulting.

Support. ...

Excellent user support, ...

... Good consulting support.

Well run center, good hardware (specific systems not specified):

This is one of the best centers I ever used and I've used many in different countries.

Very reliable high-performance computing environment. Thanks!

Among the supercomputing facilities I tried until now, NERSC excells in most aspects. I am most satisfied with the overall stability of the system. This must come from the outstanding competence of the technicians.

NERSC provides access to very high performance computing facilities on a platform with a simple interface, making development easy. ...

The computers work well and consistently. ...

Machines are available for use most of the time.

In the little time that I have been working with NERSC, everything has run very smoothly.

Avalability of resources

provide good facilities that are useable after some learning

Provides state-of-the art parallel computing platforms, and a batch environment which allows us to use our allocations in a timely fashion.

Facilities are fairly easy to use. Computation speed is very good. System reliability is good.

I have the best experience working at NERSC.

I think that all around NERSC is the most well run easy to use computer center that I have encountered so I really have no complaints (except that I would like to see emacs on the login nodes)

The machine is powerful

I just run software that other guys have developed, but I think NERSC has been very reliable and consistent over the past few years that I have been a user.

Support. Hardware availability.

The machine stays up and I can connect from anywhere with ssh.

As an all-round scientific computing center, NERSC does an excellent job.

high performance supercomputing and data storage.

Accuracy of information, platforms available and support.

Excellent user support, good hardware selection.

It has very good processors.

keeps machine up & running for a smooth working environment

The available hardware and software is very good. It meets my needs well. ...

In general, I'm very happy with NERSC services.

hardware management and consulting services

Keeps the systems running.

... and less downtime of the hardware

The overall management is excellent. ...

The system runs well and seems well-maintained

... I'm happy with the quality of the hardware.

NERSC has given me access to computing resources not available at my own institution.

Very good hardware and support.

NERSC manages its computers and mass storage system in excellent fashion.

supporting large computers.

Provide a lot of computing power, fast, secure, and always up. Really, I'm bottlenecked at the analysis side rather than the simulation side. ...

The flexibility and availability of computing resources. ...

New computing capabilities. Large scale capacity production computing. ...

I think overall NERSC provides very good support.

NERSC continues to provide consistent, high quality MPP capability and access. It is one of our primary production resources. ...

Lots of processors. Fast disk I/O on /beta disk. All disks should have this type of I/O. I do not know why you continue to use dv27-type disks when /beta is much more superior.

Big fast machines with large memory and excellent fortran environment. NERSC should continue to increase the speed and memory of its machines as the techonolgy evolves.

Documentation:

The overall job scheduling (load), user support, and documentation are the best in the world.

Provide information (as on web sites), accounts management, consulting.

Consulting, web-site, provision of a lot of good relevant information.

Consulting and web resources.

... Information services, training, account management, and consulting are all excellent.

Accuracy of information, platforms available and support.

... There is an abundance of documentation I have benefited from. ...

... online documentation pretty good

Once you get the hang of them (see below), the Web pages are generally informative and the tutorials are well written.

Information available on web pages, ...

... I have also found the online web information to be useful and clearly presented.

... Once you get the hang of them (see below), the Web pages are generally informative and the tutorials are well written.

... NERSC web pages are really, really good and well organized (except for the IBM web pages which are a disaster, but that is not your fault). ...

... I appreciate the good information on the web site as well, this is by far the most useful supercomputer web site I've dealt with.

Web site, consulting, account queries

Accuracy of information, platforms available and support.

Job scheduling / batch throughput:

The overall job scheduling (load), user support, and documentation are the best in the world.

HPSS (connection speed & space), interactive queues, hsi

I am very pleased with the performance of seaborg and the queuing system.

Provides state-of-the art parallel computing platforms, and a batch environment which allows us to use our allocations in a timely fashion.

... Reasonably quick throughput on batch jobs.

Turn-around time is very good, especially for "heavy-duty", very massively parallel jobs.

... 2. Medium to large scale parallel computing (# of CPUs per job) are both feasible at NERSC, in contrast to other supercomputing centers, where only extremely large scale computing is practically possible (queue policy is a key factor here).

Can do a lot of jobs at one time.

... The queues work efficiently, and the queue choice are well balanced. ...

... The way Seaborg is now managed makes it a pleasure to use it -- jobs usually run smoothly with less baby-sitting than at any other powerful system that my group has used. The queue structure works well. And the filesystem is also excellent.

... The priority configurtaion in Seaborg is very reasonable.

On Seaborg I find the job queues much faster and better managed than the system used on for instance Killeen in previous years. Right now I am mostly running small jobs, I am hoping this remains true when I start submitting long jobs.

The queuing system, performance of seaborg is what I am pleased with the most. ...

Seaborg:

I am very pleased with the performance of seaborg and the queuing system.

... The stability of the IBM SP in particular if compared to some large clusters is great.

I'm very pleased with the new SP machine.

The IBM-SP is a very useable machine. It is reliable, it performs well and is well configured. ...

The SP seems a good solid machine on which to do reliable runs over many processors. We've had much worse experience with large PC clusters, and it's been great to run on seaborg. ...

... The way Seaborg is now managed makes it a pleasure to use it -- jobs usually run smoothly with less baby-sitting than at any other powerful system that my group has used. The queue structure works well. And the filesystem is also excellent.

I am only a recent user of seaborg and to date I have been very happy with the system hardware/software and its performance. ...

The seaborg SP is a GREAT machine! It is well run, responsive, fast, with lots of storage and good run time. ...

... In general pvp cluster and IBM SP seem to be run well and effectively.

The queuing system, performance of seaborg is what I am pleased with the most. ...

HPSS / data storage:

HPSS (connection speed & space), interactive queues, hsi

high performance supercomputing and data storage.

I primarily use HPSS and PDSF. They both have performed very well.

I only use PDSF and HPSS but am very happy with all aspects, uptime, disk volume, batch processing, expert help ....

Every aspect concerning my STAR data analysis, from account creation to data archive and getting analysis result especially submitted batch jobs to the PDSF linux cluster were processed timely and successfully.

NERSC manages its computers and mass storage system in excellent fashion.

File storage systems ...

... The HPSS storage system is also a execellent aspect of NERSC.

PDSF:

I primarily use HPSS and PDSF. They both have performed very well.

NERSC has a wonderful set of high performance linux clusters. Building, maintaining, upgrading and user policies make my work infinitely easier than working elsewhere.

I only use PDSF and HPSS but am very happy with all aspects, uptime, disk volume, batch processing, expert help ....

I mostly use PDSF to do batch analysis of STAR data, then I transfer the reduced volume set to a local computer for detailed analysis.

PDSF

Every aspect concerning my STAR data analysis, from account creation to data archive and getting analysis result especially submitted batch jobs to the PDSF linux cluster were processed timely and successfully.

well working pdsf cluster with almost 100% uptime, no crashes

Software / user environment:

The consistent use of the "modules load" program to be able to switch between different programs/versions of a program is great.

NERSC provides access to very high performance computing facilities on a platform with a simple interface, making development easy. ...

The available hardware and software is very good. It meets my needs well. ...

... libraries ...

I am only a recent user of seaborg and to date I have been very happy with the system hardware/software and its performance. ...

Support users and applications. Willingness to work with specific applications that need special access or help. Availability of support personel.

... excellent fortran environment ...

Other:

Make up long surveys

No advice to give, we're still beginning.


What should NERSC do differently?   66 responses

Job Scheduling

Reduce wait time for long queues.

Large jobs will sit in queue too long and are effectively impossible to run. Thus from a user perspective NERSC is not a large machine. It is a small machine! This seems contrary to the intent of NERSC.

Need longer time limit for big jobs (>1600 processors)

The 8 hours queue limit on the regular queue is restrictive. The regular_long with 24 hours sounds useful, but has only 32 nodes available.

install a longer than 24 hr queue on seaborg. much longer time slots (~1 week) should be available in the queues.

Add longer queues that will allow for longer runs on fewer processors. This will cut down on waste. Perhaps require special permission for these queues if it is a problem.

I guess it would help us if the 8 hour queue would change to a 10 hour queue, as long as throughput was not too adversey affected.

... You need to offer a long queue (at least 4-8 hours) for serial jobs. Much post- processing of large parallel calculations cannot or has not been parallelized. There are also still many linear algebra/math library operations for which parallel codes have not been developed. With the demise of the Cray SV1's, there is also a need for a serial queue to run these applications on. Even when parallelization is possible, the human time involved in making all of these codes immediately parallel is expensive; computer time is not. Although some of these calculations can be done on local platforms (i.e., Linux) this is of limited use since local resources can quickly become overloaded and we may not have all of the needed libraries installed locally.

allocation and structure of queue waiting

Walltime limit ?

... and it would be nice to have a better grasp of anticipated wait times for submitted jobs.

The operators or consultants should monitor the status of the batch queues more closely. You have a wonderful visual tool at qstat/llq_seaborg - you should use it. On two occasions this spring I noticed problems that you should have caught.

Allocations / accounting:

Streamline the allocations process and make it more equitable. ERCAP proposals are nearly as complex and elaborate as contract proposals. Respect user privacy regarding allocations and time used. Balance privacy and public scrutiny?

The allocation process could be less opaque.

... The allocation process could be further streamlined. Find some way to allow more mid-year flexibility in the resource allocation process. Get away from the current allocation model (which still tends to encourage a "use-it-or-lose-it" mentality). Perhaps you should consider under-allocating and then letting some fraction of the remaining time be made available in sort of a free-for-all mode. ...

... Also the allocation process is not very transparent. Fusion (the heavy users in nonlinear MHD and gyrokinetics) have run completely out of time in July.....even though we have got about 50% more than initially allocated. We are sitting on our hands until October. We should have got more time....but this also ties in to

allocation and structure of queue waiting

The application to obtain a startup allocation was a bit lengthy. ...

The charging of the accounts is rather artificial, especially on IBM SP the real computing time is usually much smaller than the charged time.

Software:

Improve the UNIX environment to be more user friendly -- more like the standard Linux bash command line.

Provide better UNIX shell

How about allowing tcsh?

Add more functionality via grid services.

... It might be useful to have a number of frequently used application codes up and running, e.g., some large electronic structure codes, Car-Parinello codes, etc. Some of these applications are now work-horses and accessible to many users.

Maybe more application software although I should continue to explore to make sure that I just can't find some things I would like to use.

Application software for analyzing model outputs is lacking. Tools for quick analysis of model outputs will be really useful.

Documentation:

information on how to use libraries

... The more online documentation, including specific examples, the better.

The technical documentation on the NERSC web site is not always easy to find or to parse. Often one is directed to the IBM web pages which are generally far less useful than the NERSC originated pages. This was particularly an issue for me in initially porting my code to the IBM-SP2 and trying to understand options/flags/limits etc for the MPI C compiler.

I think the web pages are very good in some spots, but incomplete and difficult to locate for other topics. Perhaps the web pages need to be reorganized or linked together differently.

improve web documentation of IBM SP.

My suggestions are pretty minor(1) web pages are sometimes a big convoluted and the information is hard to find; this is relatively rare, but does happen so it comes to mind. Mind you, on the whole

The information webpages could be organized in a better fashion, ...

Provide more computing resources:

Expansion of IBM SP system, more hours allocated

Add more computing resources (more CPU's, faster CPU's, more disk space, more memory, etc.) ...

The system is generally fairly crowded; perhaps adding more CPU's would help.

more computation power, as always!

Increase hardware capacity at least 10 folds and compare with the total capacity of the NSF centers.

The major way in which NERSC could improve would be to upgrade its computing facilities more aggressively. It is surprising to me that NERSC trails the NSF centers in total computing power.

Just continue to buy the processors and disks (/beta type). The more the better.

Provide better hardware:

Processors on IB SP are getting relatively slow.

Machines with higher memory bandwidth, shorter memory latency would greatly improve performance on my codes.

faster machines (as usual!). A good balance is important, presently the CPUs are too fast for their I/O or memory bandwidth.

The present class of machines at NERSC is geared to embarrassingly parallel codes that can be run in short increments. To provide useful supercomputing capability for less parallelizable codes (10s to 100s of processors), more emphasis should be placed on single-processor speeds (vector nodes), and much longer time slots (~1 week) should be available in the queues.

Availability of large-memory not-too-massively parallel machines would continue to be a useful resource.

Big picture maximize overall research productivity in a time-share envionment....this means proving more capacity (FLOPs per year) via "cluster center" (many not-connected identical clusters of 128-256ps size) and only offering "supercomputers" (2048ps) to the limited use (> 256ps) for which they were intended. ...

Keep the PVP Cluster / maintain a PVP resource:

NERSC needs a replacement for the PVP cluster. ...

Once you get rid of Killeen, I may never use NERSC again.

Provide access to some PVP systems elsewhere. Maybe DOE should do this. The older systems are useful for some particular applications.

The PVP cluster is a useful resource that should not disappear.

Maintain a PVP capability.

Training / new user services:

See previous comment about sending more information to new users. [It would be useful to new users if they were sent an email containing information about the resources available - for instance, which machines are available to them and for which machines their usernames and passwords are valid, and maybe a summary of what the different machines are generally used for (development/visualisation..). For example, I was not aware that visualisation services are available at nersc - I'm sure this information is located on the website but if you're not looking for it you're not going to see it - even though visualisation services would be of interest to me.]

If there is a way to let the new user know how to set up the scripts to run batch jobs, know how to understand the error messages during compiling.

NERSC should go almost exclusively to web tutorials and web based training. Courses on site are just out of the question to go, since it is much too expensive to fly to the west coast.

Can they give us a tip once a week in using seaborg or programming or a little message once a week to indicate what seaborg can do?

Training activity could be increased.

NERSC response: NERSC is offering monthly training classes on the Access Grid Node. These are announced in advance on the hpcf.nersc.gov home page.

No need for change / no suggestions:

Excellent center, I wouldn't change anything

Nothing specific comes to mind. When problems do arise they are handled promptly and professionally.

No suggesions

Nothing comes to mind.

PDSF:

Pdsf=> batch queue and IO priorities need to be clearly defined.

NERSC response: There is a section in a tutorial for new users http://pdsf.nersc.gov/talks/startut050302/PDSFstarTutorial3_files/v3_document.htm) that explains how system calculates priorities. That section will be linked from the batch page as the issue of priorities is of great interest to many users.

There is no IO priorities.

There is a terrible interface with desktop computers. I cannot access my PDSF files with a GUI interface. There ways to do it such as NFS or SAMBA, but NERSC does not implement them because of security reasons. There needs to be a way for me to access my NERSC files as if they are on my laptop. AFS works well, but NERSC only supports that access for a small amount of disk space. Modern computing uses a GUI interface. NERSC needs to support that interface.

NERSC response: Security threats indeed disrupted development of software that was unifying the desktop and the compute environments. There is a new generation growing though based on the Globus toolkit. We are monitoring this development but it is not ready for the production yet. Nevertheless it is important for users to follow those developments so that the projects develop to their liking (http://www.ppdg.net/pa/ppdg-pa/idat/ and http://mrccs.man.ac.uk/research/grenade/ ). Especially the Grenade project closely matches user's requirements:
"The initial prototype will use Globus to extend the functionality of the popular KDE desktop for Linux. KDE is open source and has an architecture ideal for our purposes, featuring an XML-based framework for componentisation. KDE is layered on Qt, a cross platform C++ GUI framework featuring an elegant, powerful signal/slot mechanism for communication between components. The first demonstrator will feature single sign-on, resource discovery, and a file browser for remote file systems (we will teach KDE's browser Konqueror to speak the grid-ftp protocol). An RSL GUI and drag-and-drop job submission will follow."

The frequency of disk failure at pdsf should be improved, if possible.

NERSC response: The hardware failure rate for hard drives is comparable to the average failure rate for commodity hard-drives. It may appear artificially high as we have a large number (>>600) of them. However, in order to minimize impact of those failures on our users we closely monitor the market and adopt solutions that ease that allow for transparent drive replacements. Right now (mid-October 2002) we are finishing a conversion of the disk vaults from a software to a hardware raid (~33 done and ~5 more to go). That not only improves their performance, but also makes them more reliable and easier to replace hard drives without affecting the users.

More outreach / collaborations:

Possibly more could be done to help remote users make the best use of NERSC. Possibly many users would benefit from periodic visits, as opposed to classes. ...

It is expensive to come as a university researcher and allocate time. I think NERSC needs more partnerships on the best science areas.

communicate with other HPC closely. Sometime, solutions to problems on the same type of machines could be copied from other HPC. It will save time and human resources.

More interactive services:

See below. [Consider dedicating a few nodes to interactive shared use for debugging purposes. SDSC does this; performance on the shared nodes is assuredly terrible, but you can at least fire up totalview on a parallel job without loadleveler rejecting it due to lack of free nodes. This situation has become the bane of my existence at NERSC in recent months.]

My only real complaint is about not being able to run interactively often on Seaborg. Perhaps this congestion could be mediated by (if possible) allowing different jobs to be run on the same nodes. Instead of occupying all 16 processors on a node when I am only using 4 processors, could the other 12 be used by someone else?

Networking:

faster connection w/ mcurie (T3E)

need better Xwindows access; too slow to actually use it from here

HPSS:

Improve the reliability of the HPSS storage system. This might have been done already as I have not used the storage system since I had problems several months ago.

No inode quotas:

... NERSC should remove i-node quotas on all machines. (More disk space would also help).

Other:

Make shorter surveys

kick out stupid users, they never learn

Most of my suggestions have been made already and are really quite minor.


How does NERSC compare to other centers you have used?   62 responses

NERSC is the best / very good / overall NERSC is better:

NERSC is the best I have used.

Very favorably.

NERSC has a better SP batch environment than NPACI, where it is difficult to use ones allocation. NERSC, in theory, provides much more permanent disk space than NPACI. NERSC gives users better access to consulting staff than NPACI. NPACI has unlimited allocations on their HPSS. However, they do not allow external access to their HPSS unlike NERSC.

Excellent.

You provide the best computational and users services. I use NCSA, SDSC and PSC.

Very well!

Nersc is certainly better than Idris (the center of CNRS-France), although consulting is easier (hour and language)

Nersc has beetter support (because it is dedicated support), and a lot of batch machines available (compare to rcf). rcf (Brookhaven), cern, in2p3 (Lyon, France)

Compared Livermore Computing at LLNL, NERSC is doing a great job.

NERSC is the best I know of.

I also use SDSC and many local (university) centers. NERSC has a huge lead on all of them. SDSC is a distant second.

I also use RCF at BNL. Compared to RCF, NERSC performs much better. RCF tends to be overloaded and they often have problems with their mass storage.

I think NERSC compares very well to other centers that usually do not have such a high standard of service.

NERSC compares very well with other centers. As I said, the major problem with NERSC is system crowding; this is likely the result of the high demand caused by the quality services you provide.

PDSF beats RCF for uptime, usability, stability, support. I much prefer to work at pdsf, even though I work on RHIC experiments and RCF is the main computing hub.

the only other similar system I've used is the Jlab High Performance Cluster; NERSC (PVP cluster) is far better in every way except pure horsepower

We have extensive experience with several NPACI and some DOD supercomputer centers. In all honesty, I think these centers have many things to learn from NERSC, whereas I cannot think of anything these other centers implement that could make NERSC better than currently is. One thing that NERSC should NOT do, as unfortunately many NPACI centers do, is to keep increasing its "favoritism" towards jobs requiring an ever-increasing number of CPUs. These other centers have failed to understand that there are specific areas of excellent science where linear scaling with huge # of CPUs is merely impossible, because of the nature of the problem dealt with, not because of code deficiencies. I strongly encourage NERSC to stay away from that logic. Excellent Science needs both super-large but also medium range parallel computing.

Other computing services I have used have been operated by non-professional staff or pretty small in size. The NERSC does an outstanding job of maintaining the system.

NERSC systems operations are much more reliable that BNL computing facilities.

It is definetily more reliable than RCF at BNL.

Far superior to Brookhaven.

The availability of software at NERSC and OSC is superiour to NCSA.

I think the quality of service is very high here at NERSC

terrific! look at the poorly working rcf at BNL.

Of all the ones I used, it is the best. The old Pittsburgh supercomputer center had equally good (if not better) consulting/help, but no good web pages and the computers weren't as good. The other center I use a lot was the SDSC bluehorizon. What

NERSC gave a larger environment on which to test my software than NCSA(UIUC) did.

I've used the SDSC, and a local beowulf. I must admit beowulfs equal the computational speed of NERSC, but the storage and queue system make NERSC much easier and efficient to use. I think I used the NERSC web site just as much as the SDSC one when starting to use the SDSC facilities, a testament to the wealth of information you provide.

NERSC is the top high performance computing center in my opinion. I also compute at NCAR, ORNL, PSC, and LANL. No other center provides the response or support that NERSC does.

You have done much better in Seaborg than the San Diego Supercomputer Center does in BlueHorizon (IBM/SP) in configurating the priority of the jobs in the queue. SDSC highly favors the big jobs using many nodes while those using a single node sometimes have to wait days even in the high priority queue.

Compares very well. (San Diego)

Compared to TACC, SDSC, ORNL, PNNL NERSC has a clearer web site and a team that responds most readily to any problems.

NERSC is one of my favorite centers to use and work with. ORNL, NCAR, PSC, LLNL, LANL

Superior to RCF

Overall NERSC does a good job. I have used machines at Argonne, NCSA, and Cornell, but NERSC has been the most professional operation. However the great number of users makes it difficult to get things done at times.

Better than SDSC in consulting proficiency.

much better. for example compared with ABCC of National Cancer Institute

NERSC is the same as / mixed response:

In comparison to LANL's ACL, NERSC is a full-support operation but far less flexible to the external user.

Consulting service is better than that of PSC and San Diego, but PSC has more cycles available and each processor is faster.

I feel that NERSC is superior to RCF, which has a lot of trouble with uptime and disk storage, and is on a par with CERN, from my somewhat limited experience of CERN.

I found "startup" was better handled at NCSA. I was mailed a packed with a "quick reference" sheet which answered almost all of my questions for getting up and running on the Origin. It took considerably longer and was more work for me to port my work to the IBM-SP2. This may be because I started when the machine was still new to NERSC. NERSC has handled all aspects better than my experience with the Cray at SDSC.

We currently work with a number of centers in US and Europe (NCSA, PSC, Leibniz-Rechenzentrum Garching, Max-Planck Rechenzentrum). We haven't worked as much at NERSC as some of the others, but we've been pleased with the services at NERSC and they seem to compare well. It is often the case that the software or projects we are running require some special considerations, such as open ports for communication, or availability of large disks for short amounts of time, and we've always found NCSA to be very helpful in working with us on things like this. We really appreciate that type of flexibility towards individual projects.

compared to NCAR SCD, the consultants at NERSC are more knowledgeable and able to resolve questions, but the the online resources are not as helpful. in terms of computers, NERSC is comparable to NCAR.

I am using all three NSF lead centers (NCSA, PSC, SDSC). The professionalism with which NERSC manages its facilities exceeds theirs, as does the responsiveness of NERSC's staff. This is high praise because the NSF centers are very good in these areas too. NERSC's mass storage system as as good or better than those at the NSF centers. Where NERSC lags is in overall compute power. Seaborg has less capability than the PSC Compaq machine, Lemieux, without even taking into account the very considerable resources at NCSA and SDSC. With the new DTS system coming on line at NCSA/SDSC in the summer of 2003, NERSC is in danger of falling seriously behind. More importantly, there are major problems squarely within the DOE mission, which require several orders of magnitude more computing power than NERSC currently has.

I have only used LLNL and NERSC. Both do a great job and share many personality traits.

I have use gsfc goddard space center cray computers and have found nersc computers to be as easy to use as gsfc computers. We didn't have sp allocations at gsfc so I can't compare seaborg to theirs.

The other center I used extensively is the NCSA at UI, Urbana-Champaign. I started using NERSC again after a gap of few years (mainly as a result of NCSA doing all the things I need much better than NERSC) and have to say that it has vastly improved. It now compares quite favorably with NCSA. My only problem (complaint) now is the lack of plotting software at NERSC ( at NCSA I can use on the origin machines AVS, Techplot etc.,). The available software such as DX seem to be poorly configured (DX for instance doesn't support netcdf as it is presently configured on Seaborg).

I think you are on par with other's like SDSC (particularly this year with your improvements in expansion ratio (turn-around time / run time) on seaborg.....you should focus on "research producivity"....then you would be the best.

NERSC is less good:

FZ Juelich, Germany They provide a unique home directory for all Cray Computers. The access to the archive file system is easier, as migration and demigration is managed by the operating system.

At LRZ Muenchen the maximum runtime is 32 hours for a job and the system places no other restrictions on number of cpu, memory... I use that regularly for production runs and it is great. At lemieux at PSC there is an option to specify qsub -I on which one gets a collection of nodes for interactive use. This allows for very rapid debugging, since one bypasses the queue.

Consider dedicating a few nodes to interactive shared use for debugging purposes. SDSC does this; performance on the shared nodes is assuredly terrible, but you can at least fire up totalview on a parallel job without loadleveler rejecting it due to lack of free nodes. This situation has become the bane of my existence at NERSC in recent months.

Consulting response is longer and training courses are less frequent compared to Pittsburgh Supercomputer Center (PSC).

I prefer to take classes at a locally in-person, and was glad to a able to take a few classes at the North Carolina Supercomputer Center on parallel programming and use of an IBM SP (which is a half hour drive from my home institution)

Compared to the ORNL CCS, NERSC is not as flexible in terms of accomodating jobs that may require the use of more processors or larger CPU time.

Dealing with HPSS credentials is a problem. Changing your password at NERSC is messy. At ORNL, they run DCE natively, making password changes easy. The down side is all the extra baggage that comes with DCE. It would be nice if DOE were to standardize on an authentication/authorization infrastructure, whatever it may be.

No comparison made:

I haven't used other centers.

NERSC is the only center I've tried.

SDSC Local NCSA

FNAL computing center and university clusters.

Too early to tell

NCSA is the other center that I have most experience with, and earlier with Cornell. I have also had some experience with NPACI and Pittsburgh.

RCF. but I used PDSF more often than RCF in the past year.

RCF


NERSC provides access to very high performance computing facilities on a platform with a simple interface, making development easy. Information services, training, account management, and consulting are all excellent.