More research than anything else. We are having an occasional performance problem with one file, and I was checking the lock tables and tuneables. And realized that I might be misinterpreting "RLOWNER", since "smat-a" does not list out a separate table for it, at least that I could see.
On some earlier versions of Solaris & UV, it is possible to configure the lock tables to be too large for the memory segment, and uvregen will balk. I have not played with this at the current releases. I agree that the default for RLOWNER of 300 does not sound very taxing, but if it really is 300 table entries for each group semaphore x 40 bytes or so, that could add up to a chunk of wasted space. + Okay, I tested a couple of these changes: Changing RLOWNER from 300 to 400 has no effect on the segment size output of uvregen. Changing RLOWNER to 2000 also has no effect. Changing the RLTABSZ by 100 upped the usage by 1.7 M ( GSEMNUM=97). Likewise, bumping GSEMNUM by 10 to 107 bumped the segment size by 0.52 M. (No units, since it is not reported by uvregen. It could be bytes or words.) >From this, I deduce that RLOWNER, does not affect the size of any tables, >rather it might be a limit on the number of users that can concurrently lock a >single record using the READL statement. Not sure what else it could be. -Rick -----Original Message----- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Aaron Titus Sent: Thursday, August 15, 2013 7:20 AM To: U2 Users List Subject: Re: [U2] Universe Configuration -- I wouldn't be concerned about the default value being too high. The main reason to modify the tunables is to increase them when you are hitting a limit. Years ago, when kernels had very little shared memory in their out-of-the-box configuration, the tunables were set quite low so that Universe would function after installation. With decent sized concurrent users (or lots of phantoms) it would frequently need to be increased. The defaults now are more reasonable. smat -a will show all the lock tables; with that you can see where you are at a given point in time. Increase it if you are reaching the limit but there is no reason to lower them if you are not. *Aaron Titus* Senior Software Engineer F.W. Davison & Company, Inc. 508-747-7261 x245 ati...@fwdco.com On Wed, Aug 14, 2013 at 6:23 PM, Rick Nuckolls <r...@lynden.com> wrote: > The link to SQL makes some sense. > > My original thought was RLOWNER was to Shared Locks (RL) as RLTABSZ is to > Exclusive (RU) locks, but the default (300) seemed a little high for > tracking RL locks, especially if that is 300 x GSEMNUM. Also, the only > reporting that I can find is as a "RL" entry in the LIST.READU output, with > multiple locks on a single record appearing as a single record lock in the > "Active Group Locks" list. Interestingly, "smat -r" shows the user info > for the shared locks, but not the exclusive locks. This makes me wonder if > the configuration value is still relevant, or if the tables have been > combined. > > In that there seem to be very minimal uses for shared locks outside of > SQL, 300 seems a bit high for the average Legacy PI/OPEN install. > > Thanks, > Rick > > -----Original Message----- > From: u2-users-boun...@listserver.u2ug.org [mailto: > u2-users-boun...@listserver.u2ug.org] On Behalf Of Phil Walker > Sent: Wednesday, August 14, 2013 2:00 PM > To: U2 Users List > Subject: Re: [U2] Universe Configuration -- > > The RLOWNER parameter relates to record shared locks and were introduced > to Universe when the SQL syntax was. The value determines the number of > slots available to hold the user information of the processes holding the > shared locks. If any shared locks are held against a record an exclusive > lock, READU or FILELOCK, EXCLUSIVE will fail or take the locked clause. If > you do not use SQL or specifically request a READL lock in basic then you > can basically ignore it I believe from memory. > > Regards > > Phil > > -----Original Message----- > From: u2-users-boun...@listserver.u2ug.org [mailto: > u2-users-boun...@listserver.u2ug.org] On Behalf Of Rick Nuckolls > Sent: Thursday, 15 August 2013 6:06 a.m. > To: 'U2 Users List' > Subject: [U2] Universe Configuration -- > > Can anyone provide a cogent explanation of the RLOWNER configuration > parameter in UV? How does it relate to the GSEMNUM and GLTABSZ/RLTABSZ? > What are the contents & duration of an associated entry? Is there any way > to determine the number in use (as opposed to the configured number)? > > The manual's explanation is a bit short. Thanks, > > Rick Nuckolls > > _______________________________________________ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users > _______________________________________________ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users > _______________________________________________ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users > _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
