On Sep 27, 2012, at 8:44 AM, Reginald Beardsley <[email protected]> wrote:
> The only thing google turned up was "stop the scrub if it impacts performance > too badly" which is not really all that helpful. Or ways to speed up scrubs & > resilvers. On modern ZFS implementations, scrub I/O is throttled to avoid impacting application I/O performance. There are some kernel-level tunable parameters that can be adjusted, but AFAIK, nobody has done any characterization studies. > > In my case, I'd like to be able to run a scrub and have all the performance > hits taken by the scrub process if the system has other loads. I care that > the scrub runs, but not how fast. > > From observed behavior, it appears that the scrub is consuming too large a > share of DRAM (12 GB in this case). Is that correct and if so, is there a > way to limit the proportion of memory used by the scrub process? Data is cached in the ARC, but scrub data is placed in the MRU/LRU side of the ARC and shouldn't impact the MFU side. In most cases, the memory usage during a scrub is not a problem. Have you seen a different behaviour? -- richard > I'd like to be able to schedule scrubs regularly, but the present behavior > would require predicting when I didn't want to use the system for work. > > Thanks, > Reg -- illumos Day & ZFS Day, Oct 1-2, 2012 San Fransisco www.zfsday.com [email protected] +1-760-896-4422 _______________________________________________ OpenIndiana-discuss mailing list [email protected] http://openindiana.org/mailman/listinfo/openindiana-discuss
