Thanks, Ross, JohnS and Lamar for your kind responses. It turned out my friend is using 7200 RPM disk for his write-lots-of-little-files activity so we're looking at upgrading that to 15000 RPM or getting him a FusionIO memory card. Thank you! Aleksey On Wed, Oct 20, 2010 at 2:50 PM, Lamar Owen <lowen at pari.edu> wrote: > On Monday, October 18, 2010 09:25:41 pm Aleksey Tsalolikhin wrote: >> Hi. A friend of mine was doing real-time video decoding on >> Fedora Core 13 and he had a performance glitch (1/2 a second >> freeze) every 5-10 seconds. "top" showed flush-253:0 >> process at the moment of the freeze. > [snip] >> He also tried CentOS 5.5, and saw a "pdflush" process popping >> up with the same frequency, and resulting in a similar glitch. >> >> Any other suggestions? > > What kind of hard drive is this? How is/are your drive(s) set up? > > You need the iostat program (in the sysstat package, I think) to give you more detail; there are some pointers to its use in this list's archives. > _______________________________________________ > CentOS mailing list > CentOS at centos.org > http://lists.centos.org/mailman/listinfo/centos >