From: Nick Piggin Without disturbing the read/write ratio, increase the bathc expiry intervals. This wil have the effect of increasing latency a little, but with improved throughput. --- 25-akpm/drivers/block/as-iosched.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff -puN drivers/block/as-iosched.c~as-increase-batch-expiry drivers/block/as-iosched.c --- 25/drivers/block/as-iosched.c~as-increase-batch-expiry 2004-04-14 23:10:13.388840344 -0700 +++ 25-akpm/drivers/block/as-iosched.c 2004-04-14 23:10:13.398838824 -0700 @@ -43,7 +43,7 @@ * read_batch_expire describes how long we will allow a stream of reads to * persist before looking to see whether it is time to switch over to writes. */ -#define default_read_batch_expire (HZ / 4) +#define default_read_batch_expire (HZ / 2) /* * write_batch_expire describes how long we want a stream of writes to run for. @@ -51,7 +51,7 @@ * See, the problem is: we can send a lot of writes to disk cache / TCQ in * a short amount of time... */ -#define default_write_batch_expire (HZ / 16) +#define default_write_batch_expire (HZ / 8) /* * max time we may wait to anticipate a read (default around 6ms) _