$r->register_cleanup limits?

[Jim Woodgate <wo...@realtime.net>]

In a module I'm using register_cleanup so the client doesn't need to
wait for me to do a bunch of work.  It basically does this:

foreach (@images) {
  unless (-f $thumb{$_}) {
    &create_thumb($_);
    $r->register_cleanup(sub {&create_more_sizes($_, ...)});
  }
}

create_more_sizes will create various additional sizes to scale down a 
large picture.

This seems to work really well unless there is a large set of images,
then the cleanup handler doesn't get all the way through.  I don't see 
any warnings/errors.  (And unfortunately since the thumbnail is
created the next time someone visits create_more_sizes won't get
called unless I do explicit checks, which would cause me to actually
read the images and I was hoping to avoid that)

Anyway I'm not sure if I'm hitting a limit on the amount of time it
is taking or if I'm just registering too many cleanups.

I was thinking of $r->reset_timeout() as the first line of
create_more_size(), but thought I would check with the list first as I 
don't fully understand the ramifications.

-- 
woody@bga.com

Re: $r->register_cleanup limits (Problem Solved)

[Jim Woodgate <wo...@realtime.net>]

Doug MacEachern writes:
 > there's no limit the number of cleanups you can register, but i would
 > still push the sub {}'s into an array and register a single cleanup to
 > iterate over them.

you're right that wasn't the problem, I was passing the same
Image::Magick reference to each subroutine, and as it read in pictures
it kept using more and more memory until it ran out of and killed the
process.

I did as you suggested though and now there's only one cleanup,
thanks!

-- 
woody@bga.com

Re: $r->register_cleanup limits?

[Doug MacEachern <do...@covalent.net>]

On Tue, 6 Jun 2000, Jim Woodgate wrote:

> 
> In a module I'm using register_cleanup so the client doesn't need to
> wait for me to do a bunch of work.  It basically does this:
> 
> foreach (@images) {
>   unless (-f $thumb{$_}) {
>     &create_thumb($_);
>     $r->register_cleanup(sub {&create_more_sizes($_, ...)});
>   }
> }

there's no limit the number of cleanups you can register, but i would
still push the sub {}'s into an array and register a single cleanup to
iterate over them.
 
> create_more_sizes will create various additional sizes to scale down a 
> large picture.
> 
> This seems to work really well unless there is a large set of images,
> then the cleanup handler doesn't get all the way through.  I don't see 
> any warnings/errors.  (And unfortunately since the thumbnail is
> created the next time someone visits create_more_sizes won't get
> called unless I do explicit checks, which would cause me to actually
> read the images and I was hoping to avoid that)
> 
> Anyway I'm not sure if I'm hitting a limit on the amount of time it
> is taking or if I'm just registering too many cleanups.
> 
> I was thinking of $r->reset_timeout() as the first line of
> create_more_size(), but thought I would check with the list first as I 
> don't fully understand the ramifications.

i don't think $r->*_timeout will work properly in a cleanup, but alarm +
eval {} should be fine.  if you want to see where it's stuck, try this:
% gdb httpd <pid of spinning process>
(gdb) where
(gdb) source mod_perl-x.xx/.gdbinit
(gdb) curinfo