On Tue, Nov 4, 2008 at 12:55 PM, Bill Moran <[EMAIL PROTECTED]> wrote: > In response to "Eduardo Meyer" <[EMAIL PROTECTED]>: > >> On Tue, Nov 4, 2008 at 12:27 PM, Eduardo Meyer <[EMAIL PROTECTED]> wrote: >> > On Tue, Nov 4, 2008 at 12:18 PM, Bill Moran <[EMAIL PROTECTED]> wrote: >> >> In response to "Eduardo Meyer" <[EMAIL PROTECTED]>: >> >>> >> >>> I have some serious issue. Sometimes something happens and my disk >> >>> usage performance find its limit quickly. I follow with gstat and >> >>> iostat -xw1, and everything usually happens just fine, with %b around >> >>> 20 and 0 to 1 pending i/o request. Suddely I get 30, 40 pending >> >>> requests and %b is always on 100% (or more than this). >> >>> >> >>> fstat and lsof gives me no hint, because the type of programs as well >> >>> as the amount of 'em is just the same. >> >>> >> >>> How can I find the PID which is hammering my disk? Is there an "iotop" >> >>> or "disktop" tool or something alike? >> >> >> >> top -m io -o total >> > >> > Great, thats exactly what I was looking for, thank you a lot Mr Moran. >> >> I see syncer (40%) and bufaemon (10%) and after that, imapd. The first >> ones are kernel PIDs (36 and 37). >> >> PID USERNAME VCSW IVCSW READ WRITE FAULT TOTAL PERCENT COMMAND >> 36 root 2 2 0 31 0 31 40.79% bufdaemon >> 37 root 2 2 0 16 0 16 21.05% syncer >> 71501 vmail 4 0 0 0 0 0 12.00% imapd >> >> I guess it a symptom of some hardware problems, kernel itself is not >> supposed to do this many I/O, right? >> >> Sometimes PID 39, softdepflush, is always on top 3. > > Off the top of my head, it looks like you're exceeding what the hardware > can do. What kind of disks do you have in that system? It may be time > to get faster disks or expand to a high-performance RAID setup.
Its a: Master: ad4 <Hitachi HDP725050GLA360/GM4OA52A> Serial ATA II I still think its a hw (disk or controller) problem. I have raised the following: kern.filedelay=90 kern.dirdelay=90 kern.metadelay=90 Now, my disk usage is back to 30% > > -- > Bill Moran > http://www.potentialtech.com > -- =========== Eduardo Meyer pessoal: [EMAIL PROTECTED] profissional: [EMAIL PROTECTED] _______________________________________________ email@example.com mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-questions To unsubscribe, send any mail to "[EMAIL PROTECTED]"