On Tuesday 5 July 2011 at 18:40 Leyne, Sean wrote: > > Are you running SuperServer, Classic or SuperClassic?
It is super server, although this should not make any difference. The code that collects the stats is at a very low level. It is related to when the O/S system calls are made to physically read/write to disc. > Have you considered the effect of garbage collection? How would that have an effect? isql returns the i/o for the execution of a single statement (in this case with just a single connection to the database.) The connection only executes a single statement and, as it disconnects it grabs the mon$ i/o stats. I don't believe garbage collection can happen until after the commit, > Have you considered the cost of indirect (ie. indexes) pages which could be > updated/written? If you think about it there is no way that this can or should be relevant. The statistics are meant to indicate actual page reads and writes from disc. It should not (and does not) matter where they are from. There would be little point in stats that only returned data reads / writes and ignored, say, the i/o of updating several indexes. Physical I/O stats are collected at a very low level but they are stored at a higher level. My suspicion is that the figures are getting overwritten some how. Paul -- Paul Reeves http://www.ibphoenix.com Specialists in Firebird support ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
