On Sat, Mar 23, 2013 at 6:31 PM, Terry Ellison <te...@ellisons.org.uk> wrote:
> On 23/03/13 09:46, Matīss Roberts Treinis wrote:
>
> Memcached is distributed caching system, where as APC's user data
> cache is not. Memcached requires separate server instance (memcached)
> to operate. APC does not.
>
> Yes, but there is nothing to stop an admin of an application-dedicated
> system or VM configuring and using an in-server memcached.
>
> Also, APC's user cache is 5+ times faster
> than memcached. If some extension is to provide this functionality, it
> has to be as close as possible in possibilities and speed as APC's
> implementation has. Memcached is not and never hasn't been an
> alternative for APC, they are meant for two different jobs.
>
> I also agree that memcache is slower because it is out of process and that
> for some usecases the relative speed differences due to these context
> switches will impact application performance. Yes, they have different
> sweet-spots and operational characteristics, but for many usecases the
> relative impact will be immaterial, and memcached can be a perfectly
> acceptable substitute.
>
> Applications which are closely coupled to high APC data cache usage will
> probably stay with APC for the foreseeable future.
Hey:
APC is not a pure user data cache, the user data cache of it is a
additional function of opcodes cache, that means the implemention is
restricted by opcodes cache context.
and to be honest, I think user data cache and opcodes cache
should be separated into different modules..
Yac is a pure user data cache, doesn't have the restriction which
APC has, that is why Yac can be implemented without locks.
you can see a big performance improvement compare Yac against APC,
http://www.laruence.com/2013/03/18/2846.html (use google translate,
if you can not read chinese :))
thanks
>
> An SMA-based data cache would be a useful adjunct to O+, so I will be
> interested in this, but I just don't see this filling a show-stopper gap
> that must be addressed as a priority.
>
> <snip>
>
> Laurence, you are correct that O+ doesn't provide data caching, but what
> about memcached and the PECL packages that support it?
> http://pecl.php.net/package/memcache and
> http://pecl.php.net/package/memcached
>
>
--
Laruence Xinchen Hui
http://www.laruence.com/
--
PHP Internals - PHP Runtime Development Mailing List
To unsubscribe, visit: http://www.php.net/unsub.php
