On Thu, 7 Mar 2002, Alfred Perlstein wrote: > * Jan Grant <[EMAIL PROTECTED]> [020307 08:12] wrote: > > Something odd seems to be happening; I'd appreciate "look here" > > suggestions. I suspect mmapped pages aren't being flushed but gawd alone > > knows why. > > > > Situation: vmware2, with a "fake disk", files in the /external FS > > (/external/vmware1/nt1.*). > > > > FBSD-stable. Behaviour's been like this for quite some time (since > > around 4.3-release, I think) > [snip] > > Note: this doesn't result in ultimately broken behaviour, because those > > pages are eventually flushed on orderly shutdown. I'm just curious as to > > why sync(2) isn't forcing this. > > Afaik this is a "feature" of Linux that the emulator tries to emulate. > > From what I've _heard_ (not witnessed), Linux doesn't have the syncer > flush mmap(2)'d data on a regular basis, so in FreeBSD we emulate this > behaviour and you get the behaviour you've been seeing. > > Since, sync(2) schedules the syncer to sync out the buffers which > are marked for ignore by the syncer you don't see anything being > done. :)
Heh, cheers, I'll check that now I know what I'm after. That would explain why I couldn't replicate this using "plain" FBSD though :-) -- jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ Tel +44(0)117 9287088 Fax +44 (0)117 9287112 RFC822 [EMAIL PROTECTED] Generalisation is never appropriate. To Unsubscribe: send mail to [EMAIL PROTECTED] with "unsubscribe freebsd-hackers" in the body of the message
