10 Gigabit - Not as fast as expected?

[jgreco]

I wonder why the Linux version is different?

My (possibly incorrect) understanding is that the Linux memory management system is kind of a train wreck of amateur hour, whereas FreeBSD had a relatively clean memory management design and then some people porting ZFS who cared enough to spend the extra time to integrate it more deeply, and do all the debugging. I realize I am effectively daring someone to call me a FreeBSD bigot.

 

[Arwen]

@jgreco - You're a FreeBSD bigot!

Oh wait, if what you said is true, about both Linux memory management being a train wreck, and FreeBSD integrating ZFS deeply in to the memory management, (like Solaris), then that does not necessarily mean you are a bigot. So I have to take back my comment.


Of course, I have had problems on Solaris 10, (and maybe 11), where a newly launched program checks free memory, and does not find enough, so won't start.

The application people stopped the application so that they could make a change. On a normal reboot, ZFS ARC usage would be tiny, so the application could start easily. But, after a few days, ZFS ARC has grown to use almost all unused memory. The application people tend to think the server needs trouble shooting because something is using too much memory. That is because of the broken version of "top" installed does not break out ZFS ARC verses other users of memory.

If the stupid application would just ask for the memory, and check the return code, it would find the memory request was granted.

 

[LIGISTX]

My (possibly incorrect) understanding is that the Linux memory management system is kind of a train wreck of amateur hour, whereas FreeBSD had a relatively clean memory management design and then some people porting ZFS who cared enough to spend the extra time to integrate it more deeply, and do all the debugging. I realize I am effectively daring someone to call me a FreeBSD bigot.

So.... an update on this. Today I upgraded from 12U8 to 13U4, and my read speeds practically doubled. I am now getting a solid 4-4.5 gigabit where as on 12U8 it was more like 2-2.5 at best

I am fairly happy with this from a harddrive based array...

.