Adrian Ulrich wrote:
There was a read slowdown, in latest release of reiser4, see patch I cc'd this list on a few emails ago.I also noticed some odd slowness of reiser4
(Running 2.6.10 using the latest 2.6.10-rcsomething reiser4 patch)
That said, try extents only option of reiser4 for faster deletes.
Because reiser4 has larger files stored in tails, it packs things more tightly than reiser3, but pays a price in delete speed to do it. With extents only, no tight packing, fast deletes.
reiser3 also puts directory entries for multiple directories close to each other, and farther from the filebodies for them, compared to reiser4. This may explain some of the find speed advantage.
Still, I am curious to see more measurements in this area if you have time for it.
Did you time the sync command or? How large was the fileset created compared to RAM?
What i did:
I created a small script wich creates MANY (= 195075) directories like this: 1/[1-3]/[1-255]/[1-255]
After this, i ran 'sync && find . > /dev/null && rm -rf *'
Well, it's not a good test, but compare the speed of the 'find' and 'rm -rf' part beteween ReiserFS and Reiser4 :-/
reiser3
#./mkdirs.pl real 5m21.194s user 1m12.323s sys 4m6.740s
#find . > /dev/null real 0m6.419s user 0m0.940s sys 0m5.159s
#rm -rf * real 0m24.357s user 0m1.558s sys 0m22.797s
reiser4
#./mkdirs.pl real 6m21.996s user 1m13.395s sys 5m8.233s
#find . > /dev/null real 0m16.006s user 0m3.323s sys 0m12.676s
#rm -rf * real 5m58.963s <-- OUCH! user 0m7.962s sys 5m50.870s
