Fedor

You guys have big shoes to fill, but I hope that you're up to the task! In terms of coverage, other than the obvious and things that have already been mentioned by others, I think there is a big gap in coverage when it comes to 1) RAID cards themselves and 2) drive performance in RAID arrays - due to firmware, various drives behave very differently when under RAID conditions, and I'm not talking about RAID edition drives vs normal ones. Some more fringe sites like xbitlabs have a bit of coverage on these issues but imo they are neither thorough nor do they have my complete trust.

Because the achille's heel of RAID5 is it's write speeds, the benefits of alignment are even greater because with proper configuration write chunks are aligned and sized the same as the stripes, whereas a casual setup will have one write very possibly overlapping two stripes causing double the workload. The nature of this tweak means random I/O is helped more than sequential operations. On my old 3ware card (9550SX) without any tweaking under linux I get about 100-120mb/s writes, whereas with the tweaks it comes close to 300mb/s - suffice it to say I was surprised because most articles I've read claimed stuff like 10%-15% gains not several multiples (although the original poster here does see such gains iirc).

For the record, my RAID5 build time with an Areca 1280 and a 11TB array is about 4 hours 40 mins. When the card is powerful enough, it will take as much time as it takes for one drive to cover it's own surface. So like for example take 750GB at 75mb/s average over the surface would be very roughly with rounding errors 750000/75 = 10000s = 167mins = 2 hours 47 mins, as one example, and with an increasing amount of drives and capacity the card CPU becomes the bottleneck and the complete time grows. Of course do note that if you leave the array alone during a rebuild it will be done considerably quicker than if you try to use it at the same time. One thing on your original post about Win XP 32bit - it will not be able to see this array. Any modern linux will (32bit included), and so will Win XP 64bit, Vista 32 or 64 bit, and Win 2K+. Your question about upgrading the RAM on the card, it is primarily a huge help with RAID5 and RAID6 write speeds, cause the writes simply go into the RAM while there is space and get dumped onto the drives as fast as possible. I find it also really helps when you do something like say extract something large from the array onto itself - that's practical experience. Theoretically, it will also really help performance with many small files that can be stored in RAM more and be written as sequential chunks instead.

I second that, please do tell us how it went! Good luck!

Firstly, thanks for the info. As for the 256GB SSD being 1K USD, that was speculation on behalf of the other guy. However, it's not exactly unreasonable because prices are plummeting, and from what I understood the Samsung SSD mentioned is still a ways away. I don't really follow your point about them being similar - when have they been similar exactly? Theirs speeds aren't remotely similar and the upcoming Samsung will have a flagship model with twice the capacity of the Mtron (although by the time Samsung rolls out their model, it's possible Mtron will have their 8000 series or whatever). As for Mtron's drive, that's good news for them. Perhaps they can reclaim the throne for a while, but their jump to 130/120 is a very small step up, unlike Samsung's doubling of speed from one generation to the next. I can't help but feel that Samsung being the behemoth that it is will be able to squeeze out the little guy.

Yeah, that seems a bit slow. 9550SX with 12 Samsung 400GB: Version 1.03 ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block-- --Seeks-- Machine Size K/sec %CP K/sec %CP K/sec %CP K/sec %CP K/sec %CP /sec %CP r1k9s1.i-s-u. 4048M 208405 73 150597 42 379016 39 493.6 1 r1k9s1.i-s-u.nl,4048M,,,208405,73,150597,42,,,379016,39,493.6,1,,,,,,,,,,,,,

What type of RAID? If you're looking for a true all-hardware card, you're simply not going to find anything under $200. But you don't need something that powerful if you're only going to run say RAID0/1/10. Two port RAID 0/1. Real simple. You sure something simple with a common chipset wouldn't work like: http://www.newegg.com/Product/Product.aspx...N82E16815124027 (Silicon Image 3132) You could either email newegg or maybe just try it - wouldn't be a big financial loss. Worst come to worst you can get this and have good performance, reliability, warranty, software and support: http://www.newegg.com/Product/Product.aspx...N82E16816118087

Can he even migrate to a RAID array that will be smaller in size? The last couple of controllers I've had (3ware/LSI/Adaptec) have been unable to do this. If you asked me this about 12-14 months ago, I could answer this without a doubt. Since then, I dont remember. Typically no would be my answer. I say backup the data to tape or disk, blow away partitions, re-create, and restore data... I mean if its good enough for Dell to tell me that for their PERC cards, it's good enough for you right? I once called into techsupport for a PE2850, and they said "oops, sometimes the PERC's spit out a bad parity. You will have to backup your data and recreate your array from scratch." I from that point on, converted to all HP servers. As of late I sell enterprise class software for a storage manufacturer, no hardware for me. Wow, that's a hell of a casual attitude for such a fatal "oops". RAID5/6 without redundancy, sounds good to me

There are LOADS of RAID cards that don't work with LOADS of various mobos. However, to give you an idea, I run an Adaptec 4805SAS on my Gigabyte X38-DQ6, and I believe continuum runs an Areca 1680 on the same board as well. Bottom line, I think Gigabyte gave you that response because the risk factor is certainly there. However, in light of the X48 being just a higher-binned X38, and my Adaptec 4805SAS and continuum's Areca working on the X38, I think your chances of success are decent. However, I do suggest getting your mobo somewhere with a generous return policy if at all possible.

What type of RAID? If you're looking for a true all-hardware card, you're simply not going to find anything under $200. But you don't need something that powerful if you're only going to run say RAID0/1/10.

Can he even migrate to a RAID array that will be smaller in size? The last couple of controllers I've had (3ware/LSI/Adaptec) have been unable to do this.

Going for the silliest post of the week award are we?

It just doesn't work that way with drives - you can get lucky or unlucky with any drive model/brand. Always give a new drive a very thorough initial test period, and also if dealing with $16K worth of data, I highly suggest something with redundancy ie RAID1 and preferably frequent backups as well.

Best performance for what? Sequential speeds? Yeah, and that should be about it. For overall speeds in bonnie++ (also other things like untarring a 4.4gigabyte backup file) reading & writing, also sequential, yeah I mean it depends what your workload is, are you running databases on your HW? .. My usage is more like large files by many people being read and written at the same time. With a read-ahead far exceeding my average filesize, it would not work. As we both said, I guess it's up to the person to realise their workload will need some specific

Best performance for what? Sequential speeds? Yeah, and that should be about it.