Bart,
Sorry for asking more questions..
Consider the following scenario,
readdir("/a"); (patch populates the ncache with all contents of /a)
rename("/a", "/b"); (patch invalidates only the ncache entry for "/a")
mkdir("/a"); (patch populates the ncache for /a)
lookup("/a/b") (This could get the handle of object b that was under /a
prior to the rename!)
I guess what I am asking is shouldn't rename invalidate strings
matching entire prefixes from the ncache during a rename?
Thanks,
Murali
On Fri, 16 Jun 2006, Bart Taylor wrote:
> Attached is an updated version of the patch that just invalidates the ncache
> entries when sys-rename is called so there shouldn't be any cache
> inconsistencies. I'll submit a spearate patch to have it update properly.
>
> Bart
>
>
>
> On 6/15/06, Bart Taylor <[EMAIL PROTECTED]> wrote:
> >
> > That's a good point. Rename should at the very least invalidate both
> > entries. The old implementation of ncache did not handle this either, so
> > this will be new (although needed). I'll update the patch to invalidate the
> > two entries and send it out again, and then work on another patch to update
> > where appropriate.
> >
> > Thanks
> > Bart
> >
> >
> >
> > On 6/14/06, Murali Vilayannur <[EMAIL PROTECTED]> wrote:
> > >
> > > Bart,
> > > Do tests like dbench or concurrent directory renames and listings pass
> > > with the ncache patches?
> > > I noticed that renames of files/directories are not handled by the patch
> > > (in which case cached names of subdirectories/files under that path may
> > > have to be invalidated/updated).
> > > Thanks,
> > > Murali
> > >
> > > On Tue, 13 Jun 2006, Bart Taylor wrote:
> > >
> > > > Sorry about that. It should be attached now.
> > > >
> > > > Bart
> > > >
> > > >
> > > >
> > > >
> > > > -----Original Message-----
> > > > From: Murali Vilayannur [mailto:[EMAIL PROTECTED]
> > > > Sent: Tuesday, June 13, 2006 10:29 AM
> > > > To: Bart Taylor
> > > > Subject: Re: [Pvfs2-developers] patch: ncache.patch
> > > >
> > > >
> > > >
> > > > Bart,
> > > >
> > > > Can you resend the patch? I dont think I saw the attachment.. Perhaps
> > > the
> > > >
> > > > patch was too big for the list?
> > > >
> > > > Thanks,
> > > >
> > > > Murali
> > > >
> > > >
> > > >
> > > > On Mon, 12 Jun 2006, Bart Taylor wrote:
> > > >
> > > >
> > > >
> > > > > This patch is a reimplementation of name cache based off tcache, and
> > > it
> > > > now
> > > >
> > > > > bears a striking resemblance to the attribute cache. There was a
> > > >
> > > > > significant API change, but that did not have an effect other than
> > > > fixing
> > > >
> > > > > the calls already in place. There are no changes to the wire
> > > protocol
> > > > or
> > > >
> > > > > the storage format. It also includes perf-counter support for
> > > > monitoring.
> > > >
> > > > >
> > > >
> > > > > The state machines have several changes to use the new API, but the
> > > >
> > > > > functionality stayed the same in most places. Sys-readdir.sm and
> > > >
> > > > > sys-lookup.sm had some minor changes/additions to make ncache update
> > > >
> > > > > properly. Lookup-ncache.sm now only checks the cache for one segment
> > > of
> > > > the
> > > >
> > > > > path at a time instead of the entire path at once. The new ncache
> > > > stores
> > > >
> > > > > individual path segments independently.
> > > >
> > > > >
> > > >
> > > > > There were updates to pvfs2-client.c and pvfs2-client-core.c to
> > > accept
> > > > the
> > > >
> > > > > new ncache options and deal with them appropriately. There were also
> > > >
> > > > > additions in upcall.h and pvfs2-proc.c. Pvfs2-proc has a
> > > generalization
> > > > of
> > > >
> > > > > one of the functions to be used for both attribute cache and name
> > > cache.
> > > >
> > > > >
> > > >
> > > > > Tuning for ncache can be done with the proc files in
> > > >
> > > > > /proc/sys/pvfs2/ncache. They mimic the acache options: hard-limit,
> > > >
> > > > > soft-limit, reclaim-percentage, and timeout-msecs. The performace
> > > > counters
> > > >
> > > > > also imitate acache and are located in
> > > > /proc/sys/pvfs2/perf-counters/ncache.
> > > >
> > > > >
> > > >
> > >
> >
> >
>
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