Re: Performance Issues

Roger Cariah said: > > I'll appreciate any thoughts on this matter. Personally, I think you're read cache rate is a bit low (96%, not 99% as you claimed) -- try adding more buffers. > Im currently running an Informix based ( Informix 7.31 FC 5 Database > Engine, > D4GL ver 3.0) Database Application on a DEC Alpha ES40 Unix box running > TruUnix 4.0 F. I have roughly 20 disks on a RAID Array system which > facilitate RAID 1 mirroring as well as Informix software mirroring for my > root dbspace. During recent times, I've experienced siginificant > performance > degradation on the appliction response time yet when I run some statistics > both on the Indformix side and Unix operating system side, I see no major > violators. > > I ran an oncheck command to see whether my database was fragmented; but > most > of my tables had only one extent. > > When I did an onstat -p,my read and write cache rate were over 99% and 96% > respectively as shown below; > > Informix Dynamic Server Version 7.31.FC5 -- On-Line -- Up 26 days > 21:28:25 -- > 352256 Kbytes > > > Profile > dskreads pagreads bufreads %cached dskwrits pagwrits bufwrits %cached > 34133868 4893915 986627967 96.54 806353 2995922 221839041 99.64 > > > isamtot open start read write rewrite delete commit > rollbk > 423605965 3461139 18012746 214076922 107648943 496825 85792 107395 > 47 > > > gp_read gp_write gp_rewrt gp_del gp_alloc gp_free gp_curs > 0 0 0 0 0 0 0 > > > ovlock ovuserthread ovbuff usercpu syscpu numckpts flushes > 0 0 0 13559.67 1203.08 694 2583 > > > bufwaits lokwaits lockreqs deadlks dltouts ckpwaits compress seqscans > 2489966 0 209827275 0 0 71 61277 140953 > > > ixda-RA idx-RA da-RA RA-pgsused lchwaits > 1220643 75817 33152539 33275723 12988 > > > In running some check on my o/s, the idle time on my CPU was 99%. There > was > no major swapping or paging taking place. and extent of pageouts was > tolerable. > > VMSTAT: > > Virtual Memory Statistics: (pagesize = 8192) > procs memory pages intr cpu > r w u act free wire fault cow zero react pin pout in sy cs us > sy > id > 4 229 31 28K 1313 32K 65M 5M 8M 687K 45M 80K 8 230 400 0 > 0 > 99 > 4 234 31 28K 1133 33K 2314 276 406 0 1436 0 23 661 417 0 > 2 > 97 > 4 238 31 28K 971 33K 397 19 219 0 145 0 18 654 393 0 > 2 > 98 > 4 239 31 28K 959 33K 2415 286 410 0 1512 0 23 170 433 0 > 1 > 99 > 4 239 31 28K 959 33K 200 0 200 0 0 0 2 118 320 0 > 1 > 99 > 4 239 31 28K 959 33K 200 0 200 0 0 0 4 147 333 0 > 1 > 99 > 4 239 31 28K 959 33K 200 0 200 0 0 0 1 139 323 0 > 1 > 99 > 4 239 31 28K 947 33K 804 44 252 0 440 0 1 360 358 0 > 1 > 99 > > > > IOSTAT: > > tin tout bps tps bps tps bps tps bps tps us ni sy id > > 0 12 0 0 5 0 3 0 3 0 0 0 0 99 > 0 30 0 0 0 0 0 0 0 0 0 0 0100 > 0 30 0 0 0 0 0 0 0 0 0 0 0100 > 0 30 0 0 0 0 0 0 0 0 0 0 0100 > 0 30 0 0 0 0 0 0 0 0 0 0 1 99 > 0 30 0 0 0 0 0 0 0 0 0 0 0100 > > > Informix Dynamic Server Version 7.31.FC5 -- On-Line -- Up 23 days > 18:47:24 -- > 352256 Kbytes > > > Segment Summary: > id key addr size ovhd > class blkused blkfree > 1 1381451777 200000000 167772160 3456 R* 19542 > 938 > 2 1381451778 20a000000 192937984 3448 V 4273 > 19279 > 3 1381451779 215800000 8388608 632 M 43 > 981 > Total: - - 369098752 - > - 23858 21198 > > > (* segment locked in memory) > > > I've been doing an "update statistics" every day and have some experienced > some performance improvement intermittedly. > > This machine is 5+ years old and I'm now wondering if the hardware just > doesn't have the capaciity again > > I haven't seen anything on the database side that could be affecting > performance; but having my cpu idle 99% of the time also reveals very > little > activity on the operating system. > > Any thoughts here?? > > thanks in advance > > > The information in this communication and any attachments are deemed by > PPSL > to be confidential and may be legally privileged and protected from > disclosure. It is intended solely for the addressee. If you are not the > intended recipient, any use, review, dissemination, distribution or > copying > of this information is strictly prohibited. Please notify the sender and > delete this message and any attachments immediately from your system. > PPSL will not be held liable for any incomplete transmission of this > message > nor any delay in its receipt. > > > sending to informix-list > -- Bye now, Obnoxio "C'est pas parce qu'on n'a rien ' dire qu'il faut fermer sa gueule" - Coluche "I'm trying to see things your way, but I can't get my head up my ass" - JCH "Ogni uomo mi guarda come se fossi una testa di cazzo" - Marco I went to the airport to check in and they asked what I did because I looked like a terrorist. I said I was a comedian. They said, "Say something funny then." I told them I had just graduated from flying school. -- Ahmed Ahmed sending to informix-list