Allocating shared memory IBM S80 / AIX 4.3.3 / IDS 7.3

Does anyone know how to allocate more than 2Gb for an Informix server on an IBM S80 / AIX 4.3 with IDS 7.3 ? I obtain the following messages ... shmat: [EMFILE][24]: out of shared memory segments, check system SHMSEG shmdt: errno = 22 (5) shm creation of shmem segment failed I cannot increase the number of BUFFERS nor than the SHMVIRSIZE. Does a limit exist ? /etc/security/limits has been modified to -1 for all parameters. Does anyone know a platform with huge database server. Configuration of S80 is 16 Gbytes and 18 processors. Thanks Lo Sent via Deja.com http://www.deja.com/ Before you buy.

[This followup was posted to comp.databases.informix and a copy was sent to the cited author.] Ho, yesm I remember this puppy... not fun grepping the universe to find it. now, the results of our problem. AIX 4.3.2 does not support more than 256MB for an apps shared memory (least thats what the manual says, and so do the release notes). AIX 4.3.3 does. BUT! yes, wait for it. There is a max of 11 SHM segments per process. You can increase this but the implications didnt look good (see man shmget). Informix grabs 4 segments on startup on our machine (/ducks while tech support throws something/). Solution was to set SHMVIRTSIZE and SHMADD all the way up. Why cant you increase the SHMVIRTSIZE? just edit your config file and bounce the engine... Then help yourself to as much ram as you can spare to informix. Also, you might want to play with onmode -F during off peak times, apparently it free's unused segments though people have reported some problems to me when I asked about it. Otherwise, read the man on shmget and fear it. Unless you are a c/fortran programmer in which case it poses threat. Nice machine, drooling away at the moment, ours is a calculator in comparison. brett > Does anyone know how to allocate more than 2Gb for an Informix server > on an IBM S80 / AIX 4.3 with IDS 7.3 ? > > I obtain the following messages ... > > shmat: [EMFILE][24]: out of shared memory segments, check system SHMSEG > shmdt: errno = 22 > (5) shm creation of shmem segment failed > > I cannot increase the number of BUFFERS nor than the SHMVIRSIZE. > > Does a limit exist ? > > /etc/security/limits has been modified to -1 for all parameters. > > Does anyone know a platform with huge database server. > > Configuration of S80 is 16 Gbytes and 18 processors. > > Thanks > > Lo > > > Sent via Deja.com http://www.deja.com/ > Before you buy. >

bob wrote in message ... >[This followup was posted to comp.databases.informix and a copy was sent >to the cited author.] > >Ho, yesm I remember this puppy... not fun grepping the universe to >find it. > >now, the results of our problem. > >AIX 4.3.2 does not support more than 256MB for an apps shared memory >(least thats what the manual says, and so do the release notes). > True. >AIX 4.3.3 does. BUT! yes, wait for it. There is a max of 11 SHM segments >per process. You can increase this but the implications didnt look ?? I had heard 10!! good >(see man shmget). > >Informix grabs 4 segments on startup on our machine (/ducks while >tech support throws something/). Solution was to set SHMVIRTSIZE David gets the two handed axe out... and >SHMADD all the way up. > >Why cant you increase the SHMVIRTSIZE? just edit your config file >and bounce the engine... Then help yourself to as much ram as you can >spare to informix. Also, you might want to play with onmode -F True. >during off peak times, apparently it free's unused segments though >people have reported some problems to me when I asked about it. > Known bug with onmode -F fixed in later version. Certainly fixed in 7.31.UC4-1 which you should be on (at least this version since IBM is a tier one platform). >Otherwise, read the man on shmget and fear it. Unless you are >a c/fortran programmer in which case it poses threat. > >Nice machine, drooling away at the moment, ours is a calculator >in comparison. > >brett > >> Does anyone know how to allocate more than 2Gb for an Informix server >> on an IBM S80 / AIX 4.3 with IDS 7.3 ? >> >> I obtain the following messages ... >> >> shmat: [EMFILE][24]: out of shared memory segments, check system SHMSEG >> shmdt: errno = 22 >> (5) shm creation of shmem segment failed >> >> I cannot increase the number of BUFFERS nor than the SHMVIRSIZE. >> >> Does a limit exist ? >> >> /etc/security/limits has been modified to -1 for all parameters. >> >> Does anyone know a platform with huge database server. >> >> Configuration of S80 is 16 Gbytes and 18 processors. >> >> Thanks >> >> Lo >> >> >> Sent via Deja.com http://www.deja.com/ >> Before you buy. >>

> >AIX 4.3.2 does not support more than 256MB for an apps shared memory > >(least thats what the manual says, and so do the release notes). > > > True. Yea, but who reads em eh? lol. I was not impressed when I saw that, because I need my box up and running, not playing with data like a m$-sql server boxen. Needless to say, we tried and it worked fine. > >AIX 4.3.3 does. BUT! yes, wait for it. There is a max of 11 SHM segments > >per process. You can increase this but the implications didnt look > > ?? I had heard 10!! from da man shmat: with the additional functionality of attaching more than 11 segments when EXTSHM=ON, or the higher-performance access to 11 or fewer segments when > David gets the two handed axe out... I remember my unix tech support days, sheesh, I was in an open plan office and everytime I got off the phone I used to bang my desk. There is nothing like a highly qualified geologist arguing with you about something he has no clue about. > Known bug with onmode -F fixed in later version. Certainly fixed > in 7.31.UC4-1 which you should be on (at least this version since > IBM is a tier one platform). Um yes, but you don't work for a company who believes that IT is just an expense. Its amazing the uphill I got when I requested maintenance. 'spose I could take the box down for an hour and watch them scream. We hit this shm story on a tuesday morning as people where comming up to speed. You can imagine the chaos. I was down for 30 minutes before I found it. I lost half my hair and I think had enough coffee to keep me happy for years. All I got was, 'what do you need you could have called tech support and fixed this in seconds, we were only down for 30 mins.' *sigh* if anyone has some pointers on how to slap the maintenance ROI point thru to my board, please, I'd love the input... FYI all, maintenance in this country even with the exchange rate works out 40% cheaper over three years than an outright purchase. Aside from the VA services it provides. </rant> brett

Don't forget that AIX 4.3.3 and S80's are 64bit enabled. 7.31.UCx is 32bit. To go over 2Gb of shared memory you need the 64bit port, which I believe has only recently been ported. In article <MPG.142019d9c77fa44a9896a6@news.dbn.lia.net>, bob <bofh@mailbox.co.za> writes >> >AIX 4.3.2 does not support more than 256MB for an apps shared memory >> >(least thats what the manual says, and so do the release notes). >> > >> True. > >Yea, but who reads em eh? lol. I was not impressed when I saw that, >because I need my box up and running, not playing with data like >a m$-sql server boxen. Needless to say, we tried and it worked >fine. > >> >AIX 4.3.3 does. BUT! yes, wait for it. There is a max of 11 SHM segments >> >per process. You can increase this but the implications didnt look >> >> ?? I had heard 10!! > >from da man shmat: >with the additional functionality of attaching more than 11 segments when >EXTSHM=ON, or the higher-performance access to 11 or fewer segments when > >> David gets the two handed axe out... > >I remember my unix tech support days, sheesh, I was in an open plan >office and everytime I got off the phone I used to bang my desk. There >is nothing like a highly qualified geologist arguing with you about >something he has no clue about. > >> Known bug with onmode -F fixed in later version. Certainly fixed >> in 7.31.UC4-1 which you should be on (at least this version since >> IBM is a tier one platform). > >Um yes, but you don't work for a company who believes that >IT is just an expense. Its amazing the uphill I got when I requested >maintenance. 'spose I could take the box down for an hour and watch >them scream. > >We hit this shm story on a tuesday morning as people where comming >up to speed. You can imagine the chaos. I was down for 30 minutes >before I found it. I lost half my hair and I think had enough coffee >to keep me happy for years. All I got was, 'what do you need you >could have called tech support and fixed this in seconds, we were >only down for 30 mins.' *sigh* > >if anyone has some pointers on how to slap the maintenance ROI >point thru to my board, please, I'd love the input... > >FYI all, maintenance in this country even with the exchange rate works >out 40% cheaper over three years than an outright purchase. Aside from >the VA services it provides. > ></rant> > >brett Colin Dawson

Da voice of reason, good point there. brett > Don't forget that AIX 4.3.3 and S80's are 64bit enabled. 7.31.UCx is > 32bit. To go over 2Gb of shared memory you need the 64bit port, which I > believe has only recently been ported. > > > In article <MPG.142019d9c77fa44a9896a6@news.dbn.lia.net>, bob > <bofh@mailbox.co.za> writes > >> >AIX 4.3.2 does not support more than 256MB for an apps shared memory > >> >(least thats what the manual says, and so do the release notes). > >> > > >> True. > > > >Yea, but who reads em eh? lol. I was not impressed when I saw that, > >because I need my box up and running, not playing with data like > >a m$-sql server boxen. Needless to say, we tried and it worked > >fine. > > > >> >AIX 4.3.3 does. BUT! yes, wait for it. There is a max of 11 SHM segments > >> >per process. You can increase this but the implications didnt look > >> > >> ?? I had heard 10!! > > > >from da man shmat: > >with the additional functionality of attaching more than 11 segments when > >EXTSHM=ON, or the higher-performance access to 11 or fewer segments when > > > >> David gets the two handed axe out... > > > >I remember my unix tech support days, sheesh, I was in an open plan > >office and everytime I got off the phone I used to bang my desk. There > >is nothing like a highly qualified geologist arguing with you about > >something he has no clue about. > > > >> Known bug with onmode -F fixed in later version. Certainly fixed > >> in 7.31.UC4-1 which you should be on (at least this version since > >> IBM is a tier one platform). > > > >Um yes, but you don't work for a company who believes that > >IT is just an expense. Its amazing the uphill I got when I requested > >maintenance. 'spose I could take the box down for an hour and watch > >them scream. > > > >We hit this shm story on a tuesday morning as people where comming > >up to speed. You can imagine the chaos. I was down for 30 minutes > >before I found it. I lost half my hair and I think had enough coffee > >to keep me happy for years. All I got was, 'what do you need you > >could have called tech support and fixed this in seconds, we were > >only down for 30 mins.' *sigh* > > > >if anyone has some pointers on how to slap the maintenance ROI