Expected Transfer Speed/Latency

[LeeWB3]

(I apologize if one of the other forum areas would have been better.)

 

I am currently running a FreeNAS box with an AMD 2500+ and 4 160GB IDE drives in RAID 5 and a PCI gigabit card.  Don't honestly remember the motherboard (believe it's a NF7 board of some kind) or the gigabit card type.

 

Right this minute I am transfering files from that box to a Vista box with 680i and two SATA drives in RAID 0 array though the built in gigabit and the transfer speed is bouncing between 10 and 20 MB/s with an average of 16.8 MB/s over the last 30 minutes or so.

 

This would mostly seem fast enough (although still much slower than local disks) but in addition to bulk storage I use this drive to store pictures along with an adobe photoshop elements 6.0 catalog and to store quicken data files.  Both of those are then shared between my wife and my computers.  Even though the FreeNAS box will throughput pretty good sequential numbers the more random access necessary for quicken and the adobe catalog just flately sucks.

 

Would unRAID be any better or is this simply a network storage issue?  Thanks for your thoughts......

[Billped]

Two thoughts:

 

1. Unraid streaming/file-transfer performance is similar to what you are seeing now

2. Latency can be a problem because of drive spindown/spinup.  You can turn that off (or set it to a long time - many hours), but then your power usage goes up.

 

Unraid was designed for streaming applications, not random access.

 

All that said, I use unraid to store photos, music, etc. and don't mind the minor latency (4-5 seconds) when a drive first spins up.

 

 

Bill

[LeeWB3]

Thanks for the response. But if it was a 4-5 second latency thing I wouldn't have a problem with this.

 

I'm really thinking this is a random access issue because i'm looking at more like 30-45 seconds for photoshop elements 6.0 to fully open the catalog (of roughly 34GB spread over 15K pictures).  If I close that program it takes the same 30-45 seconds to reopen it immediatly (i.e. no spin up).  One of my 401(k) accounts in quicken (which has 15-20 transactions/month for about the last 4 years) takes about 20-30 seconds each time I switch to it.  These times are on my 6600 680i board and they're even somewhat worse on my wife's cheap Dell with a 6300 (which does have gigabit).  I also notice that scrolling around my music collection in Windows Media Center is slightly painful because it's accessing all of the album art.

 

This really makes me wonder if NAS can be good for shared catalogs and the like.

[BLKMGK]

I do not think unRAID will be faster. Your current setup has some sort of RAID going on which if it interleaves files across multiple disks will have GREATER throughput than unRAID because unRAID stores files on single disks and doesn't stripe the storage. That's fine when streaming a movie but not so fine if say fast database access is what you are after. unRAID will be limited to the fastest speed a single disk can give access - a normal RAID with striped data will be able to draw from multiple disks at once and could\should be faster. The issue with that is the difficulty when multiple drives fail or the desire to use disparate sized drives...