brs@cis.ufl.edu (Ray Seyfarth) (03/29/91)
I am curious about experiences of users of RS/6000 model 320 systems with multiple users. In particular I would like some feedback from users with about 30 X terminals attached to a 320. What kind of performance is achieved and how much memory is needed? I am interested in using X terminals in an academic setting. There would be a lot of editing and a moderate amount of other activity. Please email responses to brs@reef.cis.ufl.edu. Thanks. Ray Seyfarth
1k1mgm@kuhub.cc.ukans.edu (Christopher Gunn) (03/29/91)
In article <27718@uflorida.cis.ufl.EDU>, brs@cis.ufl.edu (Ray Seyfarth) writes: > I am curious about experiences of users of RS/6000 model 320 systems > with multiple users. In particular I would like some feedback from > users with about 30 X terminals attached to a 320. What kind of > performance is achieved and how much memory is needed? > > Ray Seyfarth I'm interested in this, too. _Personal Workstation_ [nee _MIPS_] a few months ago [January issue? I thought I had it at my desk, but I can't find it now....] had a long detailed series of articles on the 320, one of which said they really sucked air doing serious multi-user work. I copied the articles and gave them to my IBM salesman, who's looking into possible answers/rebuttals. It was unclear from the article whether the problem was inherent architecture, cache size (which would be somewhat remedied by larger cache on xy0, y >= 3), or AIX (which could at some point be fixed). It's necessary to note that _Personal Workstation_ could better be named _PC Hotrods_, and they may have some editorial bias in favor of not giving their Everex 486-using readers bad cases of RS/6000-envy. But the numbers they published were disturbing. This may all have been discussed before I discovered that this newsgroup was where the RS/6000 stuff got posted. If so, I apologize for bringing it up again.... Christopher Gunn Molecular Graphics and Modeling Lab SPAN--KUPHSX::GUNN Department of Medicinal Chemistry, Malott Hall 913-864-4428 or -4495 University of Kansas, Lawrence, KS 66045
jdh@bu-pub.bu.edu (Jason Heirtzler) (03/30/91)
In article <27718@uflorida.cis.ufl.EDU>, brs@cis.ufl.edu (Ray Seyfarth) writes: |> I am curious about experiences of users of RS/6000 model 320 systems |> with multiple users. In particular I would like some feedback from |> users with about 30 X terminals attached to a 320. What kind of |> performance is achieved.. Has anyone else noticed problems with the ethernet controller on the model 320? Some testing I've done seems to indicate that TCP throughput is limited to about 400KB/sec, which is quite slow. Even stranger is that if I reduce the size of the individual packets (say if the size of the packet changes from 1500 bytes down to 64 bytes) I still can't send much more packets/sec than with the larger packet size. The throughput would naturally decrease with smaller packets, as you would expect, but you should to be able to send more packets/sec if they're smaller. It's really odd! It is possible that our controller is still a pre-GA version, and we are getting it swapped to a newer one (part 718 1182) to see if this helps. |> I am interested in using X terminals in an academic setting. There |> would be a lot of editing and a moderate amount of other activity. |> Last week I posted a similar question, but noone responded with more than 65 simultaneous users (not xterminal users, but "generic timesharing" users, if there is such a thing) so let me ask again: Does anyone have an RS-6000 with more than 50 simultaneous users? If you do, your input would be greatly appreciated! jdh ------------------------------------------------------------------- Jason Heirtzler (617) 353-2780 jdh@bu-pub.bu.edu Information Technology Boston University ..!bu.edu!bu-pub!jdh
jfh@rpp386.cactus.org (John F Haugh II) (03/30/91)
In article <78003@bu.edu.bu.edu> jdh@bu-pub.bu.edu (Jason Heirtzler) writes: >Last week I posted a similar question, but noone responded with more >than 65 simultaneous users (not xterminal users, but "generic timesharing" >users, if there is such a thing) so let me ask again: Does anyone have >an RS-6000 with more than 50 simultaneous users? If you do, your input >would be greatly appreciated! I regularly use a S/6000 with upwards of 120 users on it. The machine is used by IBM support staff and contractors to access a database of APAR and "How To" question information. You really should contact your IBM sales representative. She will have a collection of customers who are willing to be used as references. I know from discussions on IBM internal newgroups that there are customers running over 250 users on a single machine. DISCLAIMER: I don't speak for IBM and they don't speak for me. -- John F. Haugh II | Distribution to | UUCP: ...!cs.utexas.edu!rpp386!jfh Ma Bell: (512) 832-8832 | GEnie PROHIBITED :-) | Domain: jfh@rpp386.cactus.org "I want to be Robin to Bush's Batman." -- Vice President Dan Quayle
rmilner@zia.aoc.nrao.edu (Ruth Milner) (03/31/91)
In article <19136@rpp386.cactus.org> jfh@rpp386.cactus.org (John F Haugh II) writes: >In article <78003@bu.edu.bu.edu> jdh@bu-pub.bu.edu (Jason Heirtzler) writes: >>Last week I posted a similar question, but noone responded with more >>than 65 simultaneous users (not xterminal users, but "generic timesharing" >>users, if there is such a thing) so let me ask again: Does anyone have >>an RS-6000 with more than 50 simultaneous users? If you do, your input >>would be greatly appreciated! > >I regularly use a S/6000 with upwards of 120 users on it. The machine >is used by IBM support staff and contractors to access a database of >APAR and "How To" question information. You really need to be more specific here, i.e. which *model* of RS/6000 are you using? Someone asked about using a 320 to serve a bunch of Xstations. I have no experience with Xstations, but I do know that the interactive response time on a 320 is abysmal with more than a couple of users on it, especially if one of them is running anything remotely CPU- or IO-intensive. The 530 is not bad, the 540 is quite good. Never used a 550 or any of the other high-end systems. It depends so much on what your users do, though, that the question is very difficult to respond to generally. BTW, when you're configuring any RS/6000, bear in mind that the kernel is huge compared to other UNIXes (unices?). We got our 320 with 16MB, normally just fine for our application, and when we found performance to be very disappointing IBM loaned us a 16MB board to try. Result: the application ran on average 1.5x faster, in some cases twice as fast as before. The reason was quite simply because the AIX kernel used half the original 16MB. -- Ruth Milner Systems Manager NRAO/VLA Socorro NM rmilner@zia.aoc.nrao.edu
schales@cs.tamu.edu (Douglas Lee Schales) (04/01/91)
In article <78003@bu.edu.bu.edu> jdh@bu-pub.bu.edu (Jason Heirtzler) writes: > >Has anyone else noticed problems with the ethernet controller on the >model 320? Some testing I've done seems to indicate that TCP >throughput is limited to about 400KB/sec, which is quite slow. Even >stranger is that if I reduce the size of the individual packets (say >if the size of the packet changes from 1500 bytes down to 64 bytes) I >still can't send much more packets/sec than with the larger packet >size. The throughput would naturally decrease with smaller packets, >as you would expect, but you should to be able to send more packets/sec >if they're smaller. It's really odd! > >It is possible that our controller is still a pre-GA version, and >we are getting it swapped to a newer one (part 718 1182) to see if >this helps. We've noticed that NFS on a 320 here is a real dog. We attributed it to the Ethernet card. A Sparc1+ left the 320 choking on dust when they both were writing on an NFS partition. The application was floating point intensive with about 70k of output. The Sparc was 2-3 times faster when the output was written to a file on an NFS partition, while the 320 was ~2 times faster when writing to a local disk. Our SE is checking into the problem. Doug. +---------------------------+ | Douglas Lee Schales | | schales@cs.tamu.edu | | Dept. of Computer Science | | Texas A&M University | +---------------------------+ -- +---------------------------+ | Douglas Lee Schales | | schales@cs.tamu.edu | | Dept. of Computer Science |