behavior of cache manager in version 1.10.3
mdounin at mdounin.ru
Mon May 15 13:40:21 UTC 2017
On Mon, May 15, 2017 at 08:02:18AM -0400, Michael Corn wrote:
> The documentation for proxy_cache_path states:
> The data is removed in iterations configured by manager_files,
> manager_threshold, and manager_sleep parameters (1.11.5).
> I was wondering what the behavior of the cache manager was prior to release
> 1.11.5 (specifically, in version 1.10.3).
Prior to changes in 1.11.5, cache manager removed all files it has
to remove according to "inactive" and "max_size" configured. In
some cases this caused responsiveness problems due to huge disk
activity though (for example, if max_size was changed to a smaller
value), and hence the change. Now cache manager sometimes sleeps
even if there are cache items to remove, to avoid overloading of
the IO subsystem.
> How often does the cache manager wake up to clean?
If cache manger has nothing to do, it sleeps till next expected
expiration of a cache item as per "inactive", or for 10 seconds,
whichever is sooner. That is, if there are no inactive cache
items, "max_size" will be checked once in 10 seconds.
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