It is a common error for people to think that storage is storage, but there are quite a few differences between the configuration you spec'd and a decent modular fibre-channel array. Before I ramble on I would like to add that I have that exact case, stuffed full of 400GB SATA drives at home and it's *great* (although I am currently using LVM and ext3). I will also add that all of my friends and colleagues who use, or are still testing ZFS have pretty much come to the same conclusion. It's fast and virtually indestructible. Everyone seems to love it so far.
I am a storage admin by trade and manage nearly 4000 disks and 2 dozen arrays. Your low cost solution is a good one for non-mission critical applications and low to medium I/O demands. Here is what the expensive arrays offer in addition to what your solution provides:
Hot swappable, redundant (RHS) power. RHS controllers, cache and NVRAM. 4 or even 8 loops (used in pairs) to provide two active/active 200GB paths to each disk, or 300GB for SAS. Large write cache. Most drives have 8MB or maybe 16MB cache but the array may provide anywhere from 2GB to 32GB (or more) of cache, which makes writes a *lot* faster. Intelligent pre-fetch algorithms that, combined with cache, can significantly improve read response times. Configuration tuning options. Try changing your LUN layout without downtime. Try changing your cache block size on the fly. Try turning read caching off for write intensive LUN's, turning read caching on for a few more LUN's that do sequential I/O, and bumping up the number of blocks prefetched on those LUN's...all on the fly without interruption of service. Try updating the firmware on your controllers without disruption to service. Try doing parity scrubs on your drives without disruption. Try getting more statistics from your storage than you can get with iostat or sar. I'll leave support out of the equation but it should be a consideration when designing a solution.
And now for a few notes on the CoolerMaster appliance model. How many controllers will you need to accomodate 7TB raw? And how many PCI slots will that require? Be aware that if you decide to go for maximum density (probably 750GB 7200RPM) you may be asking for quite a few IOPS per spindle. Now how about the network side of the equation. How many gig ports are you going to need? Doesn't take much to snarf a 12MB/s pipe in the disk world. And how many PCI slots will be required for those NIC's? You may have a tough time finding a motherboard that can accomodate your slot requirements *and* have enough bus/processor power to handle all that I/O, logical device overhead and filesystem overhead. While it is valid to suggest distributing load across many of these units, you may be introducing significant management overhead. Probably better off with a small number of scalable boxes that can handle a lot of disks per box.
Enough rambling. ZFS is showing significant promise. You question is a fair one, and your configuration is a good one for certain applications. But it is *very* important to compile all of your business requirements before designing a solution. And those of us who have been around for awhile have learned that sometimes the least expensive solution ends up being quite a bit more expensive than anticipated (in downtime, manhours and sometimes, actual data loss).
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It is a common error for people to think that storage is storage, but there are quite a few differences between the configuration you spec'd and a decent modular fibre-channel array. Before I ramble on I would like to add that I have that exact case, stuffed full of 400GB SATA drives at home and it's *great* (although I am currently using LVM and ext3). I will also add that all of my friends and colleagues who use, or are still testing ZFS have pretty much come to the same conclusion. It's fast and virtually indestructible. Everyone seems to love it so far. I am a storage admin by trade and manage nearly 4000 disks and 2 dozen arrays. Your low cost solution is a good one for non-mission critical applications and low to medium I/O demands. Here is what the expensive arrays offer in addition to what your solution provides: Hot swappable, redundant (RHS) power. RHS controllers, cache and NVRAM. 4 or even 8 loops (used in pairs) to provide two active/active 200GB paths to each disk, or 300GB for SAS. Large write cache. Most drives have 8MB or maybe 16MB cache but the array may provide anywhere from 2GB to 32GB (or more) of cache, which makes writes a *lot* faster. Intelligent pre-fetch algorithms that, combined with cache, can significantly improve read response times. Configuration tuning options. Try changing your LUN layout without downtime. Try changing your cache block size on the fly. Try turning read caching off for write intensive LUN's, turning read caching on for a few more LUN's that do sequential I/O, and bumping up the number of blocks prefetched on those LUN's...all on the fly without interruption of service. Try updating the firmware on your controllers without disruption to service. Try doing parity scrubs on your drives without disruption. Try getting more statistics from your storage than you can get with iostat or sar. I'll leave support out of the equation but it should be a consideration when designing a solution. And now for a few notes on the CoolerMaster appliance model. How many controllers will you need to accomodate 7TB raw? And how many PCI slots will that require? Be aware that if you decide to go for maximum density (probably 750GB 7200RPM) you may be asking for quite a few IOPS per spindle. Now how about the network side of the equation. How many gig ports are you going to need? Doesn't take much to snarf a 12MB/s pipe in the disk world. And how many PCI slots will be required for those NIC's? You may have a tough time finding a motherboard that can accomodate your slot requirements *and* have enough bus/processor power to handle all that I/O, logical device overhead and filesystem overhead. While it is valid to suggest distributing load across many of these units, you may be introducing significant management overhead. Probably better off with a small number of scalable boxes that can handle a lot of disks per box. Enough rambling. ZFS is showing significant promise. You question is a fair one, and your configuration is a good one for certain applications. But it is *very* important to compile all of your business requirements before designing a solution. And those of us who have been around for awhile have learned that sometimes the least expensive solution ends up being quite a bit more expensive than anticipated (in downtime, manhours and sometimes, actual data loss).