Messages in this thread | | | Date | Mon, 21 Sep 2015 16:05:27 -0700 (PDT) | Subject | Re: [PATCH 05/15] RDS: increase size of hash-table to 8K | From | David Miller <> |
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From: Santosh Shilimkar <santosh.shilimkar@oracle.com> Date: Sat, 19 Sep 2015 19:04:42 -0400
> Even with per bucket locking scheme, in a massive parallel > system with active rds sockets which could be in excess of multiple > of 10K, rds_bin_lookup() workload is siginificant because of smaller > hashtable size. > > With some tests, it was found that we get modest but still nice > reduction in rds_bind_lookup with bigger bucket. > > Hashtable Baseline(1k) Delta > 2048: 8.28% -2.45% > 4096: 8.28% -4.60% > 8192: 8.28% -6.46% > 16384: 8.28% -6.75% > > Based on the data, we set 8K as the bind hash-table size. > > Signed-off-by: Santosh Shilimkar <ssantosh@kernel.org> > Signed-off-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Like others I would strongly prefer that you use a dynamically sized hash table.
Eating 8k just because a module just happened to get loaded is really not appropriate.
And there are many other places that use such a scheme, one example is the AF_NETLINK socket hash table.
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