ar performing abysmally

Jim Bell Jim at JC-Bell.com
Wed Oct 15 03:23:13 UTC 2014



On 2014-10-14 10:05 AM, Brooks Davis wrote:
> On Tue, Oct 14, 2014 at 01:12:05AM -0500, Jim Bell wrote:
>> ...
>>
>> ?time ar -v -c -u -q ...? : 362.62 real         0.11 user 0.82 sys.
>> ?time ar -v -c -r -u -s ...?: 407.94 real         0.13 user 0.80 sys
>>
>> ...
> If you want to eliminate the disk as possible source I'd try doing the ar
> run on a memory disk if the inputs will fit (you should be able to send
> the output to /dev/null).

Thanks for the input!

ar doesn't like /dev/null, but I set up a ramdisk and that works great!

     time ar -v -c -r -u -s ...
         0.70 real         0.10 user         0.34 sys

Not bad for a 77MB lib.a file.

> It's worth noting that ar doesn't really do anything particularly
> complicated, ...

Yeah, truss indicated it wasn't doing much but writing.

Any pointers for what's killing my disk writes?  I'll hound my ISP, but 
would love help from folks here.

Thanks again,
-Jim




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