Re: Anonymous mapped regions increases unlimitely on spawn

[Boris-Barboris via Digitalmars-d-learn]

On Friday, 14 December 2018 at 21:22:05 UTC, unDEFER wrote:

So it looks like a bug, and I have reported about it:

https://issues.dlang.org/show_bug.cgi?id=19487


Not an expert, but you may wish to try GC.minimize() 
(https://dlang.org/phobos/core_memory.html#.GC.minimize).

Re: Anonymous mapped regions increases unlimitely on spawn

[unDEFER via Digitalmars-d-learn]

So it looks like a bug, and I have reported about it:

https://issues.dlang.org/show_bug.cgi?id=19487

Re: Anonymous mapped regions increases unlimitely on spawn

[unDEFER via Digitalmars-d-learn]

So more digging..
dtor of Thread calls in GC.collect() if thread is finished.
But it's do nothing because

bool not_registered = !next && !prev && (sm_tbeg !is this);

is always true... So how to register the thread?

Re: Anonymous mapped regions increases unlimitely on spawn

[unDEFER via Digitalmars-d-learn]

So in digging by this problem, I have made simple patch to 
druntime. I have added in druntime/src/core/thread.d to


final Thread start() nothrow

of class Thread

import core.stdc.stdio;
printf("start Thread\n");


And to

~this() nothrow @nogc

import core.stdc.stdio;
printf("detach Thread\n");

I recompiled phobos to apply changes to druntime and I see that 
"start Thread" there is, but "detach Thread" printed only at the 
end of process even if I do GC.collect().


So dtor of class Thread doesn't call on GC. Why?

Anonymous mapped regions increases unlimitely on spawn

[unDEFER via Digitalmars-d-learn]

Hello!
I have the program which uses BDB and while testing often makes 
spawn. And after 12 hours of testing bdb said:

mmap: Cannot allocate memory

But the problem that I've found that it is not BDB created too 
many maps. Watching for /proc/[PID]/maps shows that number of 
anonymous mapped regions increases on 2 every spawn process, and 
never decreases even after finishing the spawned thread.
According to logs my program made 32543 spawns for test time. And 
my /proc/sys/vm/max_map_count = 65530. So only 444 maps was 
allocated by other reasons and 65086 by spawn.


So what to do? How to make spawn decrease count of anonymous 
mapped regions?