On Mon, Dec 17 2001, Steve Lord wrote:
> On Mon, 2001-12-17 at 05:07, Jens Axboe wrote:
> > On Sun, Dec 16 2001, Eric Sandeen wrote:
> > > Congratulations, you appear to be the world's first user of the
> > > pre-allocated buffer head pool in pagebuf! :)
> > >
> > > when pagebuf initializes, it sets aside a handful of buffer heads to use
> > > in "emergency" situations, i.e. if it tries to allocate a buffer head and
> > > fails. If this happens, it takes one from this pre-allocated pool
> > > instead. If normal allocation fails, _and_ the pre-allocated pool is
> > > empty, that thread will sleep until buffer heads get replaced in the
> > > pre-allocated pool - this is what happened to you. The thread gets woken
> > > up and picks up where it left off as soon as it is able to get a
> > > buffer head allocated from the pool.
> >
> > BTW, in your 2.5 tree please drop such private pre-allocations and use
> > the mempool_* interface. bio/bio_vec allocations and highmem are already
> > using them :-)
>
> It's already gone Jens.
Very cool Steve, good job :-)
--
Jens Axboe
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