Re: [PATCH] Prelimit number of bytes to read in "vFile:pread:"

Pedro Alves
2015-08-20T14:48:46Z

On 08/19/2015 10:12 PM, Sandra Loosemore wrote:
> On 08/19/2015 11:20 AM, Gary Benson wrote:
>> Sandra Loosemore wrote:
>>> On 08/19/2015 04:50 AM, Gary Benson wrote:
>>>> Sandra, could you please try this patch on your Altera 3c120 and
>>>> on your PandaBoard? I'm interested to know what the times are
>>>> now.
>>>
>>> Wow, this patch made a big improvement! On the nios2 board the
>>> startup took 18 seconds the first time and 10 seconds on subsequent
>>> attempts -- probably some NFS-level caching? On the PandaBoard it
>>> was 3 seconds or less.
>>
>> Great :) It's in master and 7.10 now.
>>
>> Could you try Pedro's readahead patch too? It's the third one here:
>>
>> https://sourceware.org/ml/gdb-patches/2015-08/msg00489.html
>>
>> Maybe with the readahead_cache_invalidate in
>> remote_hostio_set_filesystem removed? I'm interested to see if that
>> helps any. You don't need the other two patches in that message.
>
> This didn't do anything to help; the startup time is still 10-11 seconds.

OK, that shows that the issue with that board is not really
roundtrip latency. Not that surprising given you're connected
through ethernet. Knowing it didn't slow down is already very
useful.

Thanks,
Pedro Alves