Linux NFS SSD caching

Emad R

Okay so I learned the basics, and I can do NFS
and RAID using mdadm and lets imagine I did this with 4 drives
and made RAID 10 on Linux File Server machine, how can I speed up this NFS storage by an intelligent
cache, for example I wish to add another 250 GB SSD to act as cache, how will that work ?

What examples can you give me ? some i read suggested Varnish. I wanted something more FS and tried before, so I can work on .

Thanks.

Is this the same as Tiered storage ?

Emad R

I think I found real solid solution

https://www.cyberciti.biz/faq/centos-redhat-install-configure-cachefilesd-for-nfs/
https://www.cyberciti.biz/files/linux-kernel/Documentation/filesystems/caching/cachefiles.txt

travisdh1

@Emad-R You'd cache at the LVM and/or RAID level, not at the network (NFS) level in this case. I haven't done this myself, https://rwmj.wordpress.com/2014/05/22/using-lvms-new-cache-feature/ looks like a good set of instructions. You'd start at the "Creating cache layer" section.

Dashrender

I'm sure @JaredBusch or @scottalanmiller will say I'm wrong - but RAID 10 SSD is likely already screaming fast - and unless you're running 10 Gb networking, it's likely that your networking cable is a bottleneck instead of the drive array.

Then there is what Travis mentioned - RAID level caching, not NFS mount caching is likely the real way to go.

travisdh1

@Dashrender Yeah, I was making the assumption off HDD RAID with SSD for cache. If the RAID is already SSD, then using another drive for cache is pointless.

Dashrender

@travisdh1 said in Linux NFS SSD caching:

@Dashrender Yeah, I was making the assumption off HDD RAID with SSD for cache. If the RAID is already SSD, then using wither drive for cache is pointless.

thanks - I made an assumption that he had SSDs already based on

for example I wish to add another 250 GB SSD

scottalanmiller

@Dashrender said in Linux NFS SSD caching:

but RAID 10 SSD is likely already screaming fast

If only he had that It would be faster than the cache.

Obsolesce

@Emad-R if you already have 4x SSD in a RAID 10, a single SSD will slow it down. You would need to get nvme or RAM cache. SW can do it free I believe, or another block level caching software.

scottalanmiller

@Obsolesce said in Linux NFS SSD caching:

@Emad-R if you already have 4x SSD in a RAID 10, a single SSD will slow it down. You would need to get nvme or RAM cache. SW can do it free I believe, or another block level caching software.

He doesn't, he has four Winchesters in RAID 10.

Emad R

@Emad-R said in Linux NFS SSD caching:

AID 10 on Linux File Server machine, how can I speed up this NFS storage by an intelligent
cache, for example I wish to add another 250 GB SSD to act as cache, how will tha

Yeah the RAID 10 is on HDD, due to cost effectiveness. Will check LVM since its baked in.

Unsolved Linux NFS SSD caching