How to profile the disk io performed through mmaps?

[Stanislav Sedov]

On Tue, 28 Jul 2009 17:33:59 -0700
Yuri <yuri at rawbw.com> mentioned:

> I have a file mmapped to memory area and partially modified this way.
> 
> Is there a way to know what are the actual disk writes/reads done on the 
> file in this scenario?
> Would kqueue events on file's vnode be triggered for mmapped writes?

Yes, it should be possible to monitor files written to via mmapped region
with EVFILT_VNODE kevents.  Please note, however, that changes to mmapped
region may be propagated to the files not immediately depending on the
region attributes.

-- 
Stanislav Sedov
ST4096-RIPE
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 801 bytes
Desc: not available
Url : http://lists.freebsd.org/pipermail/freebsd-hackers/attachments/20090729/ba535075/attachment.pgp