Virtual memory consumption (both user and kernel) in modern CURRENT

[Jason Evans]

On Feb 17, 2006, at 10:34 AM, Mike Jakubik wrote:
> Kris Kennaway wrote:
>> On Thu, Feb 16, 2006 at 08:23:50PM -0500, Mike Jakubik wrote:
>>
>>> And what am i trading off here? I have "/etc/malloc.conf@ -> ajz"  
>>> and my
>>> memory usage has gone up the roof. My system used to be swap  
>>> free, and now its swapping over 40 MB. Can someone explain to me  
>>> why this new malloc is better? I don't see any speed improvements.
>>
>> It's a couple of orders of magnitude faster for threaded binaries.
>> See earlier posts by the author for extensive discussion.
>
> Great, too bad only 2% of my applications are threaded. I just  
> don't see this change very positively, using 40MB of swap, where  
> before was none does not seem to me like a speed improvement. I'm  
> all for better performance of threaded apps, but the trade off  
> seems too high.

Are redzones enabled?  (They are turned on by default in CURRENT.)   
You can check by reading the output from something like:

	MALLOC_OPTIONS=P ls

Keep in mind that they use up substantial extra memory -- 32 bytes  
per allocation.  Unless you have disabled redzones, you should expect  
much higher memory usage with jemalloc than with phkmalloc.

Thanks,
Jason