Ciprian,
> On Mar 8, 2019, at 2:15 PM, Ciprian Dorin Craciun <[email protected]>
> wrote:
>
> On Fri, Mar 8, 2019 at 9:11 PM Mark Vitale <[email protected]> wrote:
>> The -dcache option for a disk-based cache does set the number of dcaches in
>> memory.
>> It has a minimum value of 2000 and max of 10000.
>
>
> Is the 100K maximum a hard limit imposed in code, or a
> "best-practice"? (I've looked in a few places and it seems that it is
> not a hard limit.)
Well, it's 10k, not 100k. The limit is enforced by afsd; see src/afs/afsd.c
routine afsd_run,
around line 2086:
2086 if (!sawDCacheSize) {
2087 dCacheSize = cacheFiles / 2;
2088 if (dCacheSize > 10000) {
2089 dCacheSize = 10000;
2090 }
2091 if (dCacheSize < 2000) {
2092 dCacheSize = 2000;
2093 }
2094 if (afsd_verbose)
2095 printf("%s: dCacheSize autotuned to %d\n", rn, dCacheSize);
2096 }
But now on more careful reading, I see this only applies when -dcache has not
been explicitly specified.
(Which, to be fair, is the normal case).
> In addition, many of the options interact with each other.
>> The best guide for how all this _really_ works is the source code - however,
>> the
>> source itself is quite confusing at times, so I feel your pain.
>
>
> Currently I go with a trial-and-error approach. :)
>
> (I'm struggling to get AFS to go over the 50MB/s, i.e. half a GigaBit,
> bandwidth... My target is to saturate a full GigaBit link...)
>
> Thanks Mark for the info,
You're welcome.
Here are some helpful commands for examining the results of your configuration
experiments:
cmdebug <client> -cache
fs getcacheparms -excessive
Regards,
--
Mark Vitale
[email protected]
_______________________________________________
OpenAFS-info mailing list
[email protected]
https://lists.openafs.org/mailman/listinfo/openafs-info
