[OpenAFS-devel] good and bad performance of memory cache

[Edward Moy]

On Thursday, February 6, 2003, at 03:09  PM, chas williams wrote:

> the default chunksize for memcache is too small.  some results i posted
> earlier about tuning memcache:
>
>
> Version 1.02c       ------Sequential Output------ --Sequential Input-  
> --Random-
> 		    -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks--
> Machine        Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP   
> /sec %CP
>
> linux/memcache=18m
> 	       256M  3669  68  7695  33  1413   7  1566  24  1739   2 218.5    
> 2
> linux/memcache=18m,chunksize=15
> 	       256M  3968  70  8966  32  2935  12  3381  50  4310   5  96.7    
> 1
>
> solaris8/memcache=146m
> 	       256M  2415  41  3054  34  1546  13  1966  17  1895   8 155.0    
> 6
> solaris8/memcache=146m,chunksize=15
> 	       256M  4666  56  6339  41  3457  20  4465  39  5447  15  87.3    
> 5

A good suggestion.  However, any value other than 13 that I make  
-chucksize, cause a kernel panic.  This is probably related to the  
problem I had with setting the blocks to 100000.
------------------------------------------------------------------------ 
--
Edward Moy
Apple Computer, Inc.
emoy@apple.com

(This message is from me as a reader of this list, and not a statement
from Apple.)