[ILUG] anyone have any experience of java thread problems on linux ?

[Hunt, Bryan]

I temporarily changed the ulimit settings to be as so ....

[root at emuse6 huntb]# ulimit -a
core file size        (blocks, -c) 0
data seg size         (kbytes, -d) unlimited
file size             (blocks, -f) unlimited
max locked memory     (kbytes, -l) unlimited
max memory size       (kbytes, -m) unlimited
open files                    (-n) 9000
pipe size          (512 bytes, -p) 8
stack size            (kbytes, -s) unlimited
cpu time             (seconds, -t) unlimited
max user processes            (-u) unlimited
virtual memory        (kbytes, -v) unlimited

Ran the test again and got identical results. 

The ulimit is allready at unlimited .... strange.

--B


-----Original Message-----
From: Padraig Brady [mailto:padraig at antefacto.com]
Sent: Wednesday, May 08, 2002 4:58 PM
To: Padraig Brady
Cc: Hunt, Bryan; Nick Murtagh; Ilug (E-mail)
Subject: Re: [ILUG] anyone have any experience of java thread problems
on linux ?


Padraig Brady wrote:
> Hunt, Bryan wrote:
> 
>> Actually guys I had ZERO as in 0 ( as in 1 less than 1 ) input into the
>> design of the product so I couldn't give a toss as to whether it is bad 
> 
>  > design or not.
> 
> Why can't you change it?
> 
>> I just get a request from my boss make this scale up past the 1018 thread
>> limit or else we ditch Linux and go with Windows or some other crap. I 
>> prefer to
>> use Linux (for various reasons) so I try to find a solution ... So 
>> thats there I
>> am coming from ... you dig ?
>> As far as I can tell the correct answer to the question was
>> cut=
>> The Solution Make the following changes:
>>
>> In /usr/include/linux/limits.h:
>>  #define NR_OPEN 1024
>>  should be
>>  #define NR_OPEN 4096
>>  In /usr/include/linux/posix_types.h:
>>  #define __FD_SETSIZE 1024
>>  should be
>>  #define __FD_SETSIZE 4096
>>  In /usr/include/bits/types.h:
>>  #define __FD_SETSIZE 1024
>>  should be
>>  #define __FD_SET_SIZE 4096
>> =cut
>>
>> Then go and recompile glibc .... hmmm looks like a whole load of fun 
> 
> 
> Which is only apparent when you mentioned
> each thread opens a socket, hence your're running
> out of files not processes.
> 
> So all you need to do is update the number of open
> files per process. The FD_SETSIZE is bogus as this is only
> used by select which you're not using.
> 
> So you shouldn't need to recompile anything,
> just ulimit -n 8192 as root? This works as
> of 2.4 I think.

Thinking a little more about it, you might run out of
local ports also?

echo "1024 32768" > /proc/sys/net/ipv4/ip_local_port_range

You may also want to increase things in /proc/sys/fs
if you have problems.

Padraig.