Re: Separating bgwriter and checkpointer

2011/9/20 Heikki Linnakangas <heikki(dot)linnakangas(at)enterprisedb(dot)com>:
> On 20.09.2011 16:49, Magnus Hagander wrote:
>>
>> Isn't there also the advantage of that work put in two different
>> processes can use two different CPU cores? Or is that likely to never
>> ever come in play here?
>
> You would need one helluva I/O system to saturate even a single CPU, just by
> doing write+fsync.

The point of Magnus is valid. There are possible throttling done by
linux per node, per process/task.
Since ..2.6.37 (32 ?) I believe .. there are more temptation to have
have per cgroup io/sec limits, and there exists some promising work
done to have a better IO bandwith throttling per process.

IMO, splitting the type of IO workload per process allows the
administrators to have more control on the IO limits they want to have
(and it may help the kernels() to have a better strategy ?)

>
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>  Heikki Linnakangas
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