SMB & CPU for fast up/download on windows

[Stux]

Well I did read it, does not mean I understand it correctly.

From what I can tell it writes data every 5 seconds to hdd. So a 10gb connection has something in range of 26gb which then needs to get transfered to hdd. More or less? Not sure, If I'm going to write 100gb to nas via 10 seconds via 20gbs conneciton then I need another few mins to copy these 100gb from SLOG to hdds, so bigger slog - better as I can pack more and write it over time?

http://www.freenas.org/blog/zfs-zil-and-slog-demystified/

 

[Stux]

client PC> ZFS Internal LOG > ZFS Pool HDD. With SLog its Client PC> ZFS internal LOG> SLOG>ZFS Pool HDD?

The SLOG -> ZFS Pool HD step never happens.

SLOG is write only, except in an abnormal pool recovery scenario, when it is read to reconstruct the data that was in-flight when the power went out (for example).

That data that is in flight is queued up to go out to the pool with the next TXG flush, but any part of that data which is sync, is ALSO written to the SLOG asap, and as soon as its flushed to the SLOG, is then confirmed as flushed to the client pc.

 

[SweetAndLow]

The SLOG -> ZFS Pool HD step never happens.

SLOG is write only, except in an abnormal pool recovery scenario, when it is read to reconstruct the data that was in-flight when the power went out (for example).

That data that is in flight is queued up to go out to the pool with the next TXG flush, but any part of that data which is sync, is ALSO written to the SLOG asap, and as soon as its flushed to the SLOG, is then confirmed as flushed to the client pc.

I second the slog being write only.

You should also Max out your ram before you ever think about a l2arc and even after that you might not benefit from it. And you should be smart enough to actually test it.

I'll also comment in your cpu selection from the start. Never get a low power cpu and then ask about performance. Your basically picking a cpu today limits performance by design. Just get a normal cpu unless you have heat limitations.



Sent from my XT1096 using Tapatalk

 

[Ericloewe]

Not actually true. There are m.2 22110 SSDs, but they're hard to get, and they don't fit in M.2 2280 slots.

http://www.tomsitpro.com/articles/sk-hynix-pe3110-enterprise-m.2-ssd-3d-nand-v2,2-1042-2.html

This is a good example of what PLP looks like ;)

Oh, those are new to me. Last time I'd checked, they were saying they needed that pseudo-standard M.3 thing to fit in a reasonable SSD and the capacitors.

 

[Pezo]

20GB is way more than I need for quick write speed so having sLog of lets say 50gb size should work perfectly

You're talking about writing 20GB? Does it really matter if that takes 10 seconds or 60?
Don't get me wrong, I love fast transfers as much as the next guy, but you should consider whether it's really worth the cost...

 

[Stux]

You're talking about writing 20GB? Does it really matter if that takes 10 seconds or 60?
Don't get me wrong, I love fast transfers as much as the next guy, but you should consider whether it's really worth the cost...

Without a SLOG i get 5MB/s. With I get 500-750MB/s.

The SLOG is just 20GB, but is continuously replaced as data is flushed to disk.

 

[Pezo]

For sync writes, yeah, but I believe that's not OP's workload.
Also your pool can actually handle 750MB/s, no?

 

[Stux]

For sync writes, yeah, but I believe that's not OP's workload.
Also your pool can actually handle 750MB/s, no?

Yes, on a good day :)