[Chris Gordon]

I’d check the exact specs of the drives inside the G-RAID enclosures. See if there are some different models that have different specs/performance.

[Chris Gordon]

It’s good to sit and explain the details of how you use the storage — give them “a day in the life” explaining the different stages in the lifecycle of the data (ingest, edit, rendering). Be sure to include typical volumes of data you’re talking about, access patterns, etc. This should help educate them some and allow to start asking you relevant questions.

First, get the terminology down. The IT SAN guys are going to be very particular about this.

– SAN: This is the Fibre Channel network connecting the server/workstation and the storage array. SAN very specifically means block storage over FC.
– If you want file based access (AFP, CIFS, NFS) over IP/ethernet, you’re talking about a NAS (Network Attached Storage).
– In the IT world, there are huge differences when you start talking SAN and NAS. If you use the wrong term, there will be a lot of confusion and a lot harder to get to the right solution.

Some more specific differences:

– IO Patterns: video work is dominated by extremely large sequential IO (reading those huge video files off disk into your editor) where as typical IT SAN usage is more often dominated by a huge number of very small random IOs.
+ Array cache is very important in the random IO situation (you can keep a lot of important blocks in cache and rarely have to hit disk in many cases), but somewhat less relevant in a video SAN (cache will never hold what you need, so you’re always hitting disk).
+ With the huge sequential IOs of video work, parity RAID (RAID 5 and 6) allow you to throw the most spindles at IO for a given number of disks. Since IO speed is going to be dictated by the disk speed and number of spindles.
+ SATA disks are fine. They come very close to FC disks for most sequential IO and give you a lot more volume per disk.

– File System (assuming FC block based SAN): Assuming you have multiple edit stations sharing the same files (the typical situation), you’ll need a clustered file system. A shared/clustered file system (many threads here about some of the different ones) that will allow multiple workstations access the same volumes (LUNs). Typically in IT SANs only a single machine can access a given volume (LUN). The array, SAN and hosts have to be configured specifically to allow the sharing and run a shared/clustered file system to allow this to all work.

– Multi-pathing: In IT SANs, you almost always (can’t think of a case where you wouldn’t) have multiple FC connections from a host to the storage array and then run a multi-pathing driver on the host to allow both failover between paths and aggregation of those paths. In a typical configuration, a host (server) connect to the SAN would have at least 2 FC HBAs in it. These would connect to different switches that comprise the SAN and then to the storage array. This gives you multiple paths between the host and the array. If one path dies, your IO goes down the other path. With some arrays and multi-path drivers, you can aggregate the paths such that if you had 2 4Gbps FC HBAs, you could use them both at the same time and get 8 Gbps of IO. I don’t know how common this is in the video editing SAN world, so I’ll defer to Bob Zelin or others on that.

Hope that helps some.

Chris

[Chris Gordon]

Have you considered the vastly different video/graphics cards that are in those two machines? 2006 to 2011 is 5 years — an eternity in video/graphics card technology. Is it also not surprising two different operating systems three generations apart (10.5 to 10.7) are going to see changes and advancements?

So if I combine much newer hardware with newer, more refined (arguably) operating system and video drives and associated libraries, I wouldn’t at all be surprised to see the newer system having more adjustments and better output. More simply stated, I’m not surprised that your newer computer is better/faster/whatever than your older computer.

Am I missing something here?

[Chris Gordon]

The out of the box Linux and Samba configs are not going to get you the best performance they can deliver. Building a system like this is going to take a lot of expertise. Things you need to look at (off the top of my head): kernel network settings, samba configurations, file system configuration, IP network tuning. This isn’t a couple of quick things someone can tell you to do over a forum — you’re going to need to spend a good bit of time reading, learning, experimenting and testing to get the most out of the system. And after you do all of that, the hardware itself may not be up to what you want as Bob mentioned.

You are probably going to need to balance two different costs:
1. The cost of your time to learn all of the different skills to build this yourself and make it work.
2. The cost to hire someone that does know all of this and can get it done quickly.

Of course, as Bob said, you may be end having to buy new/proper hardware to get the results you need.

Hope that helps.

[Chris Gordon]

Have you done any tuning of the IP stack or Samba configuration or are you just using the defaults they ship with? Have you done any tuning on the HP workstation side?

[Chris Gordon]

Unless you’re really pressured to get a new machine NOW, I’d wait to see what Apple comes out with for the new Mac Pro. If for nothing else, just to have it as an option and do an objective analysis/comparison of the different platforms. I’d also be inclined to wait on the PC side, too.

Some specific thoughts:

[Chris Gordon]

The CPU overhead occurs when actually accessing the array, not for mounting it.

Do remember that with a RAID0 (simple stripe set), if just 1 of the disks goes bad, everything is lost. Also, please don’t consider different volumes/drives on the same machine as a good backup strategy. Things like bad/failing RAM or a bad/failing power supply could corrupt any/all disks in the system. It may see like a remote case, but things like this do happen — My Murphy loves to make fun for you. Depending on your specific needs, you may be better putting those disks in a different machine and making the copies/backups over the network. This scenario removes many more failure points.

[Chris Gordon]

Can you post the script?

[Chris Gordon]

Lion defaults to 64bit whereas with Snow Leopard the kernel defaulted to being 32bit. You can open Activity Monitor and look at the “Kind” column to see what is running in 64bit mode.

[Chris Gordon]

“MacOS Extended” is HFS+.

Have you just tried permissions on the entire drive or creating some directories on the drive and giving each different owners and permissions?