Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:66478
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: error (pb1.pair.com: domain starin.biz from 207.198.105.69 cause and error)
Sender: "Nathan Bruer" <nathan.bruer@starin.biz>
To: <internals@lists.php.net>
References: <0f1001ce19ce$8ce5a260$a6b0e720$@starin.biz> <CAORXhG+U=PBACxTQJTNfR8nZWai8WYpkt=ni8OYjv29JKYWksg@mail.gmail.com> <CAMyk_AZT9jGkLeY-s3dZWuV5S8a6p=dQ_N+poUraQb4JatxM4g@mail.gmail.com>
In-Reply-To: <CAMyk_AZT9jGkLeY-s3dZWuV5S8a6p=dQ_N+poUraQb4JatxM4g@mail.gmail.com>
Date: Tue, 5 Mar 2013 14:14:22 -0600
Message-ID: <0f6601ce19de$06ead350$14c079f0$@starin.biz>
MIME-Version: 1.0
Content-Type: text/plain;
	charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Thread-Index: AQJcCX4fXpv3hZU//TS/XYhFnJOwugI1EOcVAoJRY9OXVenAgA==
Content-Language: en-us
Subject: RE: [PHP-DEV] Memory warning hook
From: nathan@starin.biz

>This is not the same at all. When are you going to run this code? =
Memory allocations happen all the time. What Nathan asked for is an =
event that is triggered when the memory consumption reaches a =
>threshold.
>
>However, there is a different solution, which is better IMHO in the =
case of
>caches: weak references. A weak reference automatically frees the =
memory of the object, when the memory is needed.
>http://php.net/manual/en/book.weakref.php.
>
>Having said that, none of these solutions scale up to multiple servers.
>This is why shared cache systems like memcached are recommended.

I agree this probably is a good solution and I personally do use it =
along with shared memory tools, however there may be cases where the dev =
may gain more benefit from having a memory-warning installable trigger =
in place. This would allow things like allowing the dev to release =
certain cache objects before others or something completely different =
that I have not thought of yet.

> Running the GC is most likely faster than most cleanup routines a user =
could run, also usually there is not that much stuff cached in PHP =
scripts. If a PHP script has "tons" of data, which it can easily throw =
>away, in memory this sounds like a smell of an bad architecture. Cache =
cache-worthy stuff in memcache or such and fetch only the data you need.
>
>Also: What should happen if the system runs out of memory while doing =
the cleanup? Anything sane doesn't sound good either.
Yes running the GC is much faster except they are two completely =
different processes... in my example the dev is keeping references to =
data for possible future use later on however it's not possible to know =
when to release these references so php's GC can collect them if the =
user does not implement something quite juristic like ticks or frequent =
function calls throughout a code base.

>You can use ticks :)
>
>http://php.net/control-structures.declare#control-structures.declare.tic=
ks

Yes Ticks are something useable (like said above) however I have found =
ticks are clunky, frequently shunned, and you'd be ticking for no reason =
most of the time.