[PATCH 0/2] tmpfs: Improve tmpfs scalability
in [Kernel]
|
Prev: 2.6.34 kernel: UDP short packet
Next: [PATCH 2/2] tmpfs: Make tmpfs scalable with caches for free blocks
From: tim on 18 May 2010 19:40 We created a token jar library implementing per cpu cache of tokens to avoid lock contentions whenever we retrieve or return a token to a token jar. Using this library with tmpfs, we find Aim7 fserver throughput improved 270% on a 4 socket, 32 cores NHM-EX system. In current implementation of tmpfs, whenever we get a new page, stat_lock in shmem_sb_info needs to be acquired. This causes a lot of lock contentions when multiple threads are using tmpfs simultaneously, which makes system with large number of cpus scale poorly. Almost 75% of cpu time was spent contending on stat_lock when we ran Aim7 fserver load with 128 threads on a 4 socket, 32 cores NHM-EX system. The first patch in the series implements the quick token jar. The second patch update the shmem code of tmpfs to use this library to improve tmpfs performance. Regards, Tim Chen -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |