On Wed, 9 Jan 2013 18:57:09 +0100, Daniel Vetter <daniel.vetter at ffwll.ch> wrote: > This partially reverts > > commit 6c085a728cf000ac1865d66f8c9b52935558b328 > Author: Chris Wilson <chris at chris-wilson.co.uk> > Date: Mon Aug 20 11:40:46 2012 +0200 > > drm/i915: Track unbound pages > > Closer inspection of that patch revealed a bunch of unrelated changes > in the shrinker: > - The shrinker count is now in pages instead of objects. > - For counting the shrinkable objects the old code only looked at the > inactive list, the new code looks at all bounds objects (including > pinned ones). That is obviously in addition to the new unbound list. > - The shrinker cound is no longer scaled with > sysctl_vfs_cache_pressure. I made a mistake and copied the wrong code in my original implementation: vfs_cache_pressure ------------------ Controls the tendency of the kernel to reclaim the memory which is used for caching of directory and inode objects. At the default value of vfs_cache_pressure=100 the kernel will attempt to reclaim dentries and inodes at a "fair" rate with respect to pagecache and swapcache reclaim. Decreasing vfs_cache_pressure causes the kernel to prefer to retain dentry and inode caches. When vfs_cache_pressure=0, the kernel will never reclaim dentries and inodes due to memory pressure and this can easily lead to out-of-memory conditions. Increasing vfs_cache_pressure beyond 100 causes the kernel to prefer to reclaim dentries and inodes. -------------------- It's not an inode or a directory and our pages directly akin to the page and buffer caches, so I should have never used vfs_cache_pressure and you have not justified why you are adding it back. > - When actually shrinking objects, the old code first dropped > purgeable objects, then normal (inactive) objects. Only then did it, > in a last-ditch effort idle the gpu and evict everything. The new > code omits the intermediate step of evicting normal inactive > objects. This is the crux of the papering, so just do this and call it what it is. -Chris -- Chris Wilson, Intel Open Source Technology Centre
