Low RAM (temporary) environment

[nakos]

Hello community,

here the configuration of my beast (just built)
- Chassis: Supermicro 4U SuperChassis 743T-665B (Suuuper-Quite!)
- Mobo: Supermicro X10SL7 (nice integrated SAS controller!)
- Proc: Intel Xeon E3-1230v3 Haswell (enough!)
- RAM: 2x8Tb Kingston 1600 ECC (enough for the moment!)
- HDD storage: Seagate 4x2Tb (Raidz2) + 5x4Tb (Raidz)
- SSD for ZIL/L2ARC: Not needed (I guess)

Now...because i'm substituting 8Gb RAM (fault) and ordering from Newegg new RAM ( is a bit tricky from Dubai) my question is...what happen if i leave the system run for 10 days with ONLY 8Gb of memory?
Apart a decrease in performance do i have to worry about something else?

Thanks in advance
nAKos

 

[cyberjock]

Probably not. 8GB of RAM seems to be the minimum for reliability concerns to be addressed. After 8GB you are buying more RAM just for performance. So for 10 days you might want to stab yourself in the eye, but your server should be fine.

 

[jgreco]

Careful, that's about 20TB usable, right? There *is* a point where 8GB will become untenable for proper system operation, but I'm pretty sure you're not quite there yet. I've beaten on a 30TB pool with 6GB without it freaking out, but I would suggest "be gentle" and "maybe don't try to use it all" as good bits of advice while you wait for your memory. So if you're going to dump 29TB worth of VM's on there I would tend to be fearful of a bad thing happening, but if you're just putting 15TB of data on there for light retrieval, there is no reason we'd expect there to be any problems. RAM is tied both to how active a pool is and how full it is (some types of stress increase rapidly as the pool fills), which isn't particularly scientific but it is more or less backed up by practical experience.

 

[nakos]

Today i'm migrating 16Tb from a QNAP NAS...
by the way only one user can access to the files (me)

Yesterday i've tried a kind of "stress" test playing a 3D full blu ray during the rsync (QNAP<->FreeNAS) and i didn't notice any bottleneck or performance degradation...means FreeNAS is amazing :)

I keep in mind your consideration and cross the finger nothing bad happen!!! the memory should be here in a couple of weeks