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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>I’m running in to a situation where I believe the filesystem cache settings are screwing things up. Based on iozone tests I’m not getting near the throughput I should for large 4gb+ files with multiple writing processes. It is a complex interaction of the number of dirty pages in filesystem cache in combination with small blocksize of the filesystem. I’m still trying to figure this out but I can now get these machines to tip over with just iozone. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m actively working on how to refactor this code base to use GDAL WriteBlock but in absence of a solution there I’m wondering if there’s anyway to get GDAL writing using O_DIRECT?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>-ethan<o:p></o:p></p></div><PRE>This electronic communication and any attachments may contain confidential and proprietary
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