memcache key double escaped
mdounin at mdounin.ru
Thu Feb 26 16:17:02 MSK 2009
On Thu, Feb 26, 2009 at 01:40:58PM +0100, Xavier Grangier wrote:
>> It's expected as nginx escapes $memcached_key before passing it to
>> memcached. It escapes " ", "%", %00-%1F.
> Thanks for your reply. Yes I could see from source that memcache module
> escape the key.
> But seems to me weird behaviour to escape values that are already
The memcached module have to be able to deal with mostly arbitrary
$memcached_key, and therefore it has to escape space and control
characters to avoid violation of memcached protocol. To make this
escaping one-to-one it's also required to escape '%'.
> It's not a problem if memcache user notice this. I'm pretty
> sure this leads to lots of cache miss.
I agree that this deserves a bit more documentation.
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