Re: [Sqlgrey-users] [SPAM] Re: Patches for SQLgrey

[Lionel B. <lio...@bo...>]

Karl O. Pinc a écrit, le 08/18/2009 06:53 PM :
> [...]
>> delay * (last_clean_time / max_allowed_clean_time).
>>     
>
> this does not make sense to me.

My mistake I meant :

delay * (max_allowed_clean_time / last_clean_time).

it would make the cleanup time converge towards a value around
max_allowed_clean_time (which should really be called
target_cleanup_time). As said previously it's not as simple as that but
I use this kind of algorithm to setup the refresh period of RSS feeds in
a custom RSS reader and it gets a very good compromise between not
refreshing them too often and not often enough even with more or less
unpredictable content changes (which is very similar to our constraints
: don't cleanup too often to avoid putting unnecessary load on the DB
and enough to avoid blocking too long and also take the irregular
traffic pattern into account).

Lionel