On Jun 30, 2010, at 6:52 PM, Craig A. Berry wrote:
>
> On Jun 28, 2010, at 4:32 PM, Mark Berryman wrote:
>
>> Sometime between Perl 5.8.6 and 5.12.1 a memory leak was introduced into
>> Perl and it appears to be in the glob function. The following should
>> reproduce the problem on any VMS system:
>>
>> @dirs = glob('SYS$COMMON:[000000]*.DIR');
>>
>> for (;;) {
>> foreach (@dirs) {
>> s|\[000000\]|\[|;
>> $_ = substr($_, 0, rindex(uc($_), '.DIR')) . ']';
>> @files = glob($_ . '*.*;*');
>> }
>> }
>>
>> Execute this and then repeatedly hit control-T to watch your memory
>> consumption climbing. Let it run long enough and it will eventually abort
>> due to insufficient virtual memory.
>>
>
> I can confirm that it chews memory pretty fast (about 4,000 pages every 5
> seconds on my rx2600). There is a Perl_vms_start_glob() function in
> [.vms]vms.c if anyone is hankering after a session with the heap analyzer and
> wants to know where to look. I hope to look into this at some point but
> can't commit to when.
>
I found it.
In VMS.C, the routine Perl_flex_stat_int allocates memory twice without ever
releasing it. Here are the two instances:
fileified = PerlMem_malloc(VMS_MAXRSS);
temp_fspec = PerlMem_malloc(VMS_MAXRSS);
Simply adding the appropriate calls to PerlMem_free at the exit point seems to
have fixed the problem.
