I had the following kernel parameters changed over the weekend: SDELSIM 256 to 1024 SEMOPM 64 to 100 SEMUME 64 to 1024 SHMMNI 2048 to 4096 SEMMNI 2048 to 4096 SEMMSL 256 to 1024
And the problem has not occurred since! I have reviewed the documentation on each of the above parameters in hopes of determining which parameter was set incorrectly. SDELSIM - The default number of file descriptors per process. (Referred to as NOFILES in the UV documentation.) I had set SDELSIM to exceed MFILES plus the 8 internal UV files. HDESLIM (the maximum number of file descriptors a user is allowed to have open) was left at the default value of 1024. SEMOPM - The maximum number of semaphore operations per semop (2) call. Although not a parameter mentioned in the UV documentation I had concluded from some Unix documentation that the value of 100 was unnecessarily large and had reduced the value to 64. The default value is 10. SEMUME - The maximum number of Undo entries per Undo structure. Also not a parameter mentioned in the UV documentation, a reading (mis-reading) of the Unix documentation led me to conclude that the value was unnecessarily large. Since I have now learned that the default value is 1024 this change is suspect. SHMMNI - The maximum number of shared memory segments that may exist in the system at one time. The UV documentation recommends setting this to a number greater than the maximum number of concurrent Universe users plus 2. Our UV user count has not exceeded 700 users in the last few months. SEMMNI - The maximum number of semaphore sets. The UV documentation states that Universe requires 2 semaphore sets. The ipcs -s command reports that our system uses 7. SEMMSL - The maximum number of semaphores per set. The UV documentation states that this should be at least equal to FSEMNUM + GSEMNUM + 5. On our system that total is 152. I still am not sure which parameter(s) were the source of the problem. And I intend to leave well enough alone so I may never know for sure. In any case I hope that if someone else encounters the same problem they can benefit from my experience. I want to thank everyone who offered help and took the time to make suggestions. Vance Dailey -----Original Message----- From: Vance Dailey [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 03, 2004 5:23 PM To: '[EMAIL PROTECTED]' Subject: UV command failing mystery We are having a very strange intermittent problem with the UV command not working from Unix. Occasionally, after a user logs into Unix (without noticing anything unusual) typing "UV" simply returns the user to the UNIX shell almost instantly. When the problem occurs it seems to affect everyone who logins in and attempts to go into Universe for a period of time and then the problem seems to resolve itself. Any users who logged into Unix during that period of time still can not go into Universe but new logins work fine. The problem seems to be with Universe. Unix commands work fine and when we have tried executing other Universe commands which normally can be run from Unix they fail also. The Unix login script seems to run fine. When the problem occurs users already in Universe notice no problems. No unusual locks or performance problems have been noticed. The problem does not seem to be load related since it happens at apparently random times including times when very few users are logged in. We have been running 9.6.2.2 on DG/UX for several years and have never had the problem until the last couple of months. The only thing that may be suspicious is some changes we made to some kernel and UV config settings a few weeks prior to the first reported problem. The following changes were made: (KERNEL) SDELSIM 2048 TO 256 SEMOPM 100 TO 64 SEMUME 1024 TO 64 SHMMNI 4096 TO 2048 SEMMNI 4096 TO 2048 (UV CONFIG) MFILES 56 TO 200 T30FILE 8000 TO 200 (we have no dynamic files) FSEMNUM 101 TO 50 GSEMNUM 211 TO 97 GLTABSZ 150 TO 75 RLTABSZ 150 TO 75 MAXRLOCK 100 TO 74 Any help solving this puzzle would be greatly appreciated. Thanks, Vance Dailey -- u2-users mailing list [EMAIL PROTECTED] http://www.oliver.com/mailman/listinfo/u2-users
