Planning a move to SSD with iSCSI for my big stuff, wondering what others are doing with large files. I did some testing at the office and I thought I'd share it here so u guys can see how much normal drives suck arse

http://adam.qgl.org/iscsi/iscsi.htm

Jim has some other stats on the SSD which are pretty cool using the same thing.

the same test on that little ocz vertex I nabbed yesterday:

There is some massive differences there!

SSD for boot drive for the win!!

Thats decent performance from the ISCSI, from all ive read, the best you will get is 120-160mb a sec.

but, those drives natively on that server would be way faster than 100mb a sec, ive tested with the same server and get over 300mb a sec from SAS drives in a raid mirror, the iscsi is limiting it to about 100mb a sec.

It is a bit of a waste of fast drives though, I can get 100-105 mb from a hardware iscsi unit using only sata drives in the it. The raid setup of the unit didnt seem to make much difference, i got about the same speed from raid 5 and raid 10, you hit the limit of iscsi pretty easily.

Also, the unit I was setting up had 802.3 (LACP) link aggregation over 1gb ethernet connections, with LACP setup on a HP switch, but in a performance test, it wont ever use both links becuase one stream of data will only ever go over 1 link. When the device is being accessed from multiple sources as it would in a real life setup, the link aggregation makes a big difference.

ISCSI is awesome though, and unless you need realy fast disk performance, it works great. I've setup a vmware esx server using just iscsi for storage, and it worked great. You'd want to go fibre channel though if you want realy fast performance.

etherchannel bonding would've let a single data transfer go over both nics viper

also here's a hdtune test on a hp eva 4400 vraid 5 lun for shits and giggles:

etherchannel bonding would've let a single data transfer go over both nics viper

Realy? everywhere I read says that even with link aggregation it only ever uses one physical nic per transfer.

also what are you referring to when you say iscsi limit viper? term's tests there are nearly maxing our gbit connection, that's not an iscsi limitation

Yeah thats what i meant, its not an iscsi limitation, more of a limit of 1gb ethernet iscsi.

the big thing about iSCSI is you need to get to the gbit limit before it becomes useful, then its faster than all my local drives at large writes and random writes, but I suspect doing lots of small writes my drive would shit on it. For that reason I kinda favour it for storage rather than OS, hence the SSD as well.

The other thing, all the NAS reviews are quite funny, none of them mention the importance of Jumbo frames to getting the speeds you need out of it. My iSCSI at home I'm only getting 30mb/sec from cuz its a shit hub, I've ordered a 108 from auspcmarket, which is a little netgear beauty that supports jumbo frames, has 8 ports, and only 100 odd bucks.

this must make the chix in y0r office so wet

Damn you Jim! You were supposed to say it SUXXXXXXXXX.

Such a waste of money for such miniscule help with instant gratification, it could go to far better use feeding starving children or something.

DELL PowerEdge R710 with 6 x 146GB 15k SAS HDD in RAID1 & RAID1+0;

RAID1


RAID1+0

pffft tickles

At 64Mb I got pretty much the same speeds :)

thats pretty sweet.

Our disk I/O here is fucked.

Thats from the article I posted earlier, thats what I was getting at. But thats specific to VMware esx though.

ah yeh as you said that is talking about a vmware-specific issue where only a single tcp connection can be used per target, thus the channel bonding will only ever utilise a single nic in a bond

pfft I only work in 64 mb files these days :P

That is 6 x 300GB SAS Seagates in ten

naa, you're confused.

NAS x 5 7200 RPM drives in Raid5 running iSCSI for keepable data

SSD on the box running OS (can be trashed whenever)

thats like a 2k solution

upgradeable too, as larger drives become available and cheaper

we use a similar solution in the office for general storage, it's a readynas 1RU with 4 hot swap drive bays. unfortunately it doesn't provide iscsi targets natively, we just use it via smb and nfs. when we bought it a year or so ago it had 500gb disks, a few months back I replaced them with 1.5tb, nice easy capacity upgrade

http://www.legitreviews.com/article/992/7/

Jim have any upgrades helped here?


/me wanty cheapo awesome performance ;)

last edited by koopz at 21:54:54 21/Jun/09