10Gbyte ~ 80Gbit, i don´t know if 50Gbit is possible you have SO cpu time to read and write many things not just memory, check filesystem cache, etc. etc. etc., maybe you can´t get this speed with just 80Gbit memory 2011/2/15 A. Krijgsman <a.krijgsman@xxxxxxxxxxxx>: > Just ran memcheck 2 weeks ago. > > If you triple-lane your memory you get 10GByte (!) per second memory. > ( This is memory from 2010 ;-) 1333 Mhz ) > > -----Oorspronkelijk bericht----- From: Roberto Spadim Sent: Tuesday, > February 15, 2011 3:29 PM To: Zdenek Kaspar Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: high throughput storage server? > 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 > -- > 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
