Re: [9fans] fossil+venti performance question

["steve@quintile.net" <steve@quintile.net>]

I too see this, and feel, no proof, that things used to be better. I.e. the first time I read a file from venti it it very, very slow. subsequent reads from the ram cache are quick.

I think venti used to be faster a few years ago. maybe another effect of this is the boot time seems slower than it used to be.

sorry to be vague.

-Steve





> On 5 May 2015, at 15:47, KADOTA Kyohei <lufia@me.com> wrote:
> 
> Thanks Anthony.
> 
>> I bet if you re-run the same test twice in a
>> row, you’re going to see dramatically improved
>> performance.
> 
> I try to re-run ‘iostats md5sum /386/9pcf’.
> Read result is very fast.
> 
> first read result is 152KB/s.
> second read result is 232MB/s.
> 
>> Your write performance in that test isn’t really
>> relevant: they’re not hitting the file system at all.
> 
> I think to write 1GB data to filesystem:
> 
>    iostats dd -if /dev/zero -of output -ibs 1024k -obs 1024k -count 1024
> 
> Write result of dd is 31MB/s.
> But this test may just write to fossil. It may not write to venti.
> 
>> I’m not sure why you’d see a difference in a
>> fossil+venti setup of a different size, but the
>> partition size relationships, and the in-memory
>> cache size relationships, are what’s mostly important.
> 
> My hardware has 2GB memory.
> Plan 9 configurations are almost default. (except /dev/sdC0/bloom)
> To increase memory size is difficult,
> because memory size is determined by public QEMU/KVM service plan.
> 
> —
> kadota