git: kernel - vm - Change inactive target to 1/4 memory instead of 1/2 memory.

[Johannes Hofmann]

Johannes Hofmann <johannes.hofmann at gmx.de> wrote:
> Matthew Dillon <dillon at apollo.backplane.com> wrote:
>> :On my troublesome 2GB machine, the inactive memory is now ~= 750M, which
>> :is about 1/3 of RAM, quite far from the 1/4 target.
>> :
>> :-- 
>> :Francois Tigeot
>> 
>>    It's just a target for the pageout daemon, it isn't something the
>>    machine tries to hold itself to.
>> 
>>    Guys... everyone.  Please don't try to interpret the values for
>>    the active & inactive queues.  Even a good chunk of the analysis of
>>    the swap space use is wrong.  There's absolutely nothing wrong with
>>    the machine paging stuff out to swap.  The issue is only whether it
>>    does so to the degree that later pageins effect performance.
>> 
>>    Avalon, for example, usually has 200-400MB of idle data swapped out
>>    which it basically never touches.  It doesn't effect avalon's
>>    performance.
> 
> One point is probabely whether swap is on a disk with otherwise high
> IO rate. On my single disk system it is clearly a performance problem 
> if program data is paged out due to filesystem activity because then
> the paging in is very slow.
> 
> I can trigger this situation with
>        hammer cleanup
> but also with
>        find / -type f | xargs md5

This got fixed with 69adbed48cd5565446e8013fcc5131405a9e7c05

Cheers,
Johannes