first, run memtest86 (if you use x86 cpu) check ram memory speed my hp (ml350g5 very old: 2005) get 2500MB/s (~20 Gbits/s) maybe ram is a bottleneck for 50gbits.... you will need a multi computer raid or stripe fileaccess operations (database on one machine, s.o. on another...) for hobby = SATA2 disks, 50USD disks of 1TB 50MB/s the today state of art, in 'my world' is: http://www.ramsan.com/products/3 2011/2/15 Zdenek Kaspar <zkaspar82@xxxxxxxxx>: > Dne 15.2.2011 0:59, Matt Garman napsal(a): >> For many years, I have been using Linux software RAID at home for a >> simple NAS system. Now at work, we are looking at buying a massive, >> high-throughput storage system (e.g. a SAN). I have little >> familiarity with these kinds of pre-built, vendor-supplied solutions. >> I just started talking to a vendor, and the prices are extremely high. >> >> So I got to thinking, perhaps I could build an adequate device for >> significantly less cost using Linux. The problem is, the requirements >> for such a system are significantly higher than my home media server, >> and put me into unfamiliar territory (in terms of both hardware and >> software configuration). >> >> The requirement is basically this: around 40 to 50 compute machines >> act as basically an ad-hoc scientific compute/simulation/analysis >> cluster. These machines all need access to a shared 20 TB pool of >> storage. Each compute machine has a gigabit network connection, and >> it's possible that nearly every machine could simultaneously try to >> access a large (100 to 1000 MB) file in the storage pool. In other >> words, a 20 TB file store with bandwidth upwards of 50 Gbps. >> >> I was wondering if anyone on the list has built something similar to >> this using off-the-shelf hardware (and Linux of course)? >> >> My initial thoughts/questions are: >> >> (1) We need lots of spindles (i.e. many small disks rather than >> few big disks). How do you compute disk throughput when there are >> multiple consumers? Most manufacturers provide specs on their drives >> such as sustained linear read throughput. But how is that number >> affected when there are multiple processes simultanesously trying to >> access different data? Is the sustained bulk read throughput value >> inversely proportional to the number of consumers? (E.g. 100 MB/s >> drive only does 33 MB/s w/three consumers.) Or is there are more >> specific way to estimate this? >> >> (2) The big storage server(s) need to connect to the network via >> multiple bonded Gigabit ethernet, or something faster like >> FibreChannel or 10 GbE. That seems pretty straightforward. >> >> (3) This will probably require multiple servers connected together >> somehow and presented to the compute machines as one big data store. >> This is where I really don't know much of anything. I did a quick >> "back of the envelope" spec for a system with 24 600 GB 15k SAS drives >> (based on the observation that 24-bay rackmount enclosures seem to be >> fairly common). Such a system would only provide 7.2 TB of storage >> using a scheme like RAID-10. So how could two or three of these >> servers be "chained" together and look like a single large data pool >> to the analysis machines? >> >> I know this is a broad question, and not 100% about Linux software >> RAID. But I've been lurking on this list for years now, and I get the >> impression there are list members who regularly work with "big iron" >> systems such as what I've described. I'm just looking for any kind of >> relevant information here; any and all is appreciated! >> >> Thank you, >> Matt >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-raid" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> > > If you really need to handle 50Gbit/s storage traffic, then it's not so > easy for hobby. For good price you probably want multiple machines with > lots hard drives and interconnects.. > > Might be worth to ask here: > Newsgroups: gmane.comp.clustering.beowulf.general > > HTH, Z. > > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- Roberto Spadim Spadim Technology / SPAEmpresarial -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
