[DRBD-user] Multi-threaded on-line verification

Lars Ellenberg lars.ellenberg at linbit.com
Tue May 26 11:41:56 CEST 2015

Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.


On Sun, May 24, 2015 at 08:33:13PM +0200, Ben RUBSON wrote:
> > Le 22 avr. 2014 à 14:40, Lars Ellenberg <lars.ellenberg at linbit.com> a écrit :
> > 
> > On Mon, Apr 21, 2014 at 11:11:09AM +0200, Ben RUBSON wrote:
> >> Hello,
> >> 
> >> Let's assume that we have a resource which contains several volumes.
> >> When an on-line verification is launched, all volumes are verified
> >> together, but it seems that the job is made by only one thread.
> >> The bottleneck in the on-line verification are not the disks, but the
> >> CPU, as it must deal with many (for example) crc32c operations.
> >> 
> >> So my question is, could we think about an implementation which would
> >> start one verification thread for each volume ?
> >> It would dramatically speed-up on-line verification (for my own case,
> >> with 4 volumes in 1 resource, it would decrease verification time from
> >> 56 hours to 14 hours).
> > 
> > iirc, when we implemented it, the kernel crypto api was supposed
> > to get asynchronous hash support "soon", so we did not bother to add our
> > own threading/async layer over this.
> > 
> > Guess that "soon" is very relative.
> > 
> > Yes, we can add that as feature request
> > somewhere on our (not so short) todo list.
> 
> Hello,
> 
> Any news regarding this feature request, did you think about it ?

It sure is somewhere on our todo list.
That does not help you much, though :-/

-- 
: Lars Ellenberg
: http://www.LINBIT.com | Your Way to High Availability
: DRBD, Linux-HA  and  Pacemaker support and consulting

DRBD® and LINBIT® are registered trademarks of LINBIT, Austria.
__
please don't Cc me, but send to list   --   I'm subscribed



More information about the drbd-user mailing list