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<div style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">I think I found the document you are talking about. In general I believe most of it still applies. I can make the following comments on it about Spectrum Scale: </div><div dir="ltr" data-setdir="false"><div><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">
</p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">1 - There was an effort to simplify Spectrum Scale tuning, and tuning of worker1Threads should be replaced by tuning workerThreads instead. Setting workerThreads, will auto-tune about 20 different Spectrum Scale configuration parameters (including worker1Threads) behind the scene. </p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"> </p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">2 - The Spectrum Scale pagepool parameter defaults to 1Gig now, but the most important thing is to make sure that you can fit all the IO into the pagepool. So if you have 512 threads * 1 MB you will need 1/2 Gig just to do disk IO, but if you use 4MB that becomes 512 * 4 = 2Gig just for disk IO. I would recommend setting the pagepool to 2x the size of this if you are using direct IO so 1 Gig or 4 Gig for the example sizes I just mentioned. </p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">
</p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">3 - One consideration that is important is sizing the initial DB2 database size correctly, and when the tablespace needs to grow, make sure it grows enough to avoid constantly increasing the tablespace.</p><p style="margin: 0px; padding: 0px; color: rgb(8, 7, 7); font-family: Salesforce Sans, Arial, sans-serif; font-size: 13px; font-style: normal; font-weight: 400; letter-spacing: normal; text-align: left; text-indent: 0px; text-transform: none; white-space: pre-wrap; word-spacing: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">The act of growing a database throws GPFS into buffered IO which can be slower than directIO. If you need the database to grow all the time, I would avoid using direct IO and use a larger GPFS pagepool to allow it cache data. Using directIO is the better solution.</p></div><div><br></div><div dir="ltr" data-setdir="false">Jim Doherty<br></div></div><div><br></div>
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On Monday, June 7, 2021, 11:03:26 AM EDT, Wally Dietrich <wallyd@us.ibm.com> wrote:
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Hi. Is there documentation about tuning DB2 to perform well when using Spectrum Scale file systems? I'm interested in tuning both DB2 and Spectrum Scale for high performance. I'm using a stretch cluster for Disaster Recover (DR). I've found a document, but
the last update was in 2013 and GPFS has changed considerably since then.
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<div class="yiv0216751806">Wally Dietrich</div>
<div class="yiv0216751806"><a rel="nofollow noopener noreferrer" ymailto="mailto:wallyd@us.im.com" target="_blank" href="mailto:wallyd@us.im.com" class="yiv0216751806">wallyd@us.ibm.com</a></div>
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</div>_______________________________________________<br>gpfsug-discuss mailing list<br>gpfsug-discuss at spectrumscale.org<br><a href="http://gpfsug.org/mailman/listinfo/gpfsug-discuss" target="_blank">http://gpfsug.org/mailman/listinfo/gpfsug-discuss</a><br></div>
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