Daniel, Do you have the same recommendations for a Sun TSM server? We have a Sun Fire 6800 with 4 TSM instances per domain for a total of 3 domains and 4GB RAM. Our current buffpool size is 65535 and cache hit % is 98.42.
Thanks, Brian Brian Scott EDS - GCE-GM Global Client Engineering GM MS 3234 750 Tower Drive Troy, MI 48098 * phone: +01-248-265-4596 (8-365) * mailto:[EMAIL PROTECTED] -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Daniel Sparrman Sent: Thursday, January 20, 2005 10:44 AM To: ADSM-L@VM.MARIST.EDU Subject: Re: Cache Hit % below 99% Hi First of all, the q db f=d bufpool setting is not KB... it's database pages(4096 byes or 4KB) which means that if you set it to 524288, you have assigned 2GB of memory as database bufferpool. Second, you should check to see that you have free memory available for the bufpool. If not, your database bufferpool will get swapped down to the paging space and your performance will degrade. This is easily done with "svcmon". Third, check your maxperm and minperm settings aswell. They control how much memory is allowed for filesystem caching. Normally, theese are set to 40 min and 80 max which means file system caching can steal all your memory. Also set the -H parameter within vmtune to 1 so that you You should also check your maximum allowed allocation of memory. Default, AIX has it set to 80% of physical memory. This means you have 20% of memory not utilized(or 800MB of memory). This is an old setting that was supposed to protect the kernel from running out of memory. Theese day however when AIX systems has alot more memory than in the early days you can easily set the maximum allocatable memory to 95%, leaving 5% of memory as protection for AIX kernel usage. This setting is set with "vmtune -M". For some of the operations above you will need the vmtune command. To check your min and maxperm settings, enter vmtune. To change them, enter vmtune -p "minimum file system cache in percentage of physical memory" -P "Maximum file system cache in percentage of physical memory" -H 1 Vmtune also has alot of other great settings which should make it possible to tune the system even further. Some of the VM settings has a large impact on system performance. So you should be careful with what parameters you change. Best Regards Daniel Sparrman ----------------------------------- Daniel Sparrman Chef Utveckling & Drift Exist i Stockholm AB Propellervägen 6B 183 62 TÄBY Växel: 08 - 754 98 00 Mobil: 070 - 399 27 51 "Warren, Matthew (Retail)" <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <ADSM-L@VM.MARIST.EDU> 2005-01-20 16:32 Please respond to "ADSM: Dist Stor Manager" <ADSM-L@VM.MARIST.EDU> To ADSM-L@VM.MARIST.EDU cc Subject Re: Cache Hit % below 99% ? For a long time I have believed (fairly sure originally told by IBM) that the method is to increase the buffpool size untill cache hit goes over 99% Talking to a colleague, we really don't see how reducing bufpool size can increase the cache hit% Can anyone explain what we are missing? Thanks, Matt. _-'-_ -|- -----Original Message----- From: ADSM: Dist Stor Manager [mailto:[EMAIL PROTECTED] On Behalf Of Joni Moyer Sent: Thursday, January 20, 2005 2:51 PM To: ADSM-L@VM.MARIST.EDU Subject: Re: Cache Hit % below 99% Hello! I just wanted to thank everyone for suggestions and help with this matter! I changed the bufpoolsize to 419430, which is 10% of the physical memory, and then reset the bufpool and now my cache hit % is 100%. At this point, until I see otherwise, I am going to conclude that I had the bufpoolsize setting too high at 524288. I will continue to monitor the cache hit % of the database, but I believe the problem to be solved. Thank you again! ******************************** Joni Moyer Highmark Storage Systems Work:(717)302-6603 Fax:(717)302-5974 [EMAIL PROTECTED] ******************************** "Curtis Stewart" <[EMAIL PROTECTED] AWSON.COM> To Sent by: "ADSM: ADSM-L@VM.MARIST.EDU Dist Stor cc Manager" <[EMAIL PROTECTED] Subject .EDU> Re: Cache Hit % below 99% 01/20/2005 09:33 AM Please respond to "ADSM: Dist Stor Manager" <[EMAIL PROTECTED] .EDU> What is your buffpool setting? Run "query option" and look for the buffpoolsize. Look in the dsmserv.opt file and read the comments about this parameter, then look in the server manual for this too. [EMAIL PROTECTED] Joni Moyer <[EMAIL PROTECTED]> Sent by: "ADSM: Dist Stor Manager" <ADSM-L@VM.MARIST.EDU> 01/20/2005 07:19 AM Please respond to "ADSM: Dist Stor Manager" <ADSM-L@VM.MARIST.EDU> To ADSM-L@VM.MARIST.EDU cc Subject Cache Hit % below 99% Hello All! I have noticed that the cache hit % is below 99%. This is a newly defined TSM 5.2.2.5 server on an AIX 5.2 OS. Are there any special parameters/definitions that could contribute to the percentage being so low? Thanks! Available Space (MB): 24,576 Assigned Capacity (MB): 19,484 Maximum Extension (MB): 5,092 Maximum Reduction (MB): 15,000 Page Size (bytes): 4,096 Total Usable Pages: 4,987,904 Used Pages: 45,207 Pct Util: 0.9 Max. Pct Util: 0.9 Physical Volumes: 3 Buffer Pool Pages: 131,072 Total Buffer Requests: 132,692 Cache Hit Pct.: 95.15 Cache Wait Pct.: 0.00 Backup in Progress?: No Type of Backup In Progress: Incrementals Since Last Full: 0 Changed Since Last Backup (MB): 0.73 Percentage Changed: 0.41 ******************************** Joni Moyer Highmark Storage Systems Work:(717)302-6603 Fax:(717)302-5974 [EMAIL PROTECTED] ******************************** ___________________________ Disclaimer Notice __________________________ This message and any attachments are confidential and should only be read by those to whom they are addressed. If you are not the intended recipient, please contact us, delete the message from your computer and destroy any copies. Any distribution or copying without our prior permission is prohibited. Internet communications are not always secure and therefore Powergen Retail Limited does not accept legal responsibility for this message. The recipient is responsible for verifying its authenticity before acting on the contents. Any views or opinions presented are solely those of the author and do not necessarily represent those of Powergen Retail Limited. Registered addresses: Powergen Retail Limited, Westwood Way, Westwood Business Park, Coventry, CV4 8LG. Registered in England and Wales No: 3407430 Telephone +44 (0) 2476 42 4000 Fax +44 (0) 2476 42 5432
