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So, the context is a pair of new Dell 24 core servers installed this year, running 2.6.32-431.1.2.0.1.el6.x86_64. <BR>
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This replaced older Dell servers running I don't remember what. <BR>
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Both old and new servers ran about 200,000 web service queries a day using Tomcat6 and Progress OpenEdge. <BR>
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The new servers, while faster at DB updates, will several times a month, usually during prime high volumes in early afternoon, exhibit a period of 3 seconds of all DB updates being frozen. When we've chased it down, it seems the DB has completed a checkpoint, and issued a sync call afterwards, and that freezes everyone until it completes. <BR>
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The older servers, while not as fast, didn't exhibit this behavior. <BR>
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I may be wrong about the sync being the culprit; that's what the timings in the DB logs seem to indicate. <BR>
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Is there any tuning parameters which would affect the amount of time for a sync to complete on a busy server? <BR>
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Neal Rhodes<BR>
MNOP Ltd. <BR>
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