http://bugs.php.net/bug.php?id=19749
It's been playing on my mind recently that this bug
hasn't been addressed; the problem was how to guess
precisely what limit to set for mmaping when doing
something like readfile().
[note that some comments are missing from the bugdb
for that bug]
Well, we can solve the problem by allowing the
sysadmin to decide, as you can see in my patch
against PHP 5:
http://www.php.net/~wez/mmap-limit.diff
The default limit is 8MB. If the limit is set to 0,
no limit is applied.
This is separate from memory_limit, so PHP could
potentially use double the default memory amount for a
short period of time. This is still better than allowing
it to eat all the RAM when someone decides to readfile()
large media files for example.
--Wez.
Wez,
I have played with mmap() in the past. I found that mapping in relatively
small blocks such as 1MB does not really hurt performance. I suggest not to
add yet another INI option but to do it with smaller blocks. I think even
256KB wouldn't make a big difference.
Andi
At 10:10 PM 4/20/2004 +0100, Wez Furlong wrote:
http://bugs.php.net/bug.php?id=19749
It's been playing on my mind recently that this bug
hasn't been addressed; the problem was how to guess
precisely what limit to set for mmaping when doing
something likereadfile().
[note that some comments are missing from the bugdb
for that bug]Well, we can solve the problem by allowing the
sysadmin to decide, as you can see in my patch
against PHP 5:http://www.php.net/~wez/mmap-limit.diff
The default limit is 8MB. If the limit is set to 0,
no limit is applied.This is separate from memory_limit, so PHP could
potentially use double the default memory amount for a
short period of time. This is still better than allowing
it to eat all the RAM when someone decides toreadfile()
large media files for example.--Wez.