Well, that's essentially my point. SSD's seem like a cost-effective alternative to expensive RAM and less complex (fewer parts) than RAID-0. I've had jobs, however, that generated over 150 GB in temp files and ran out of space (not fun). So, an 80 GB SSD disk isn't big enough. That's why I was curious about the configuration.
Also, we run binarized tables and language models (KenLM) from a RAID-0, which recovers 50-75% of the lost performance compared to memory-loaded text tables and models. It would seem like a fast SSD over iodrive/PCIe would shift the bottleneck to the IO-to-memory bus. I don't see much advantage to installing all of Linux on SSD over well-planned and configured mounts. Then again, a server configuration is under 4 GB, so maybe a complete install is just easier. Tom On Tue, 19 Apr 2011 16:16:49 +0000, "Moses Odd" wrote: Hi, ideally swap and tmp have to stay in fast disks, why not in ram disk or SSD ? See this http://en.wikipedia.org/wiki/File:Ddrdrive_x1.jpg [1] http://en.wikipedia.org/wiki/Solid-state_drive [2] some commercial producer http://www.fusionio.com/products/iodrive/ [3] http://www.fusionio.com/products/iodriveduo/ [4] http://www.ocztechnology.com/ocz-revodrive-pci-express-ssd.html [5] http://www.ramsan.com/products [6] http://www.3dnow.net/phpBB2/viewtopic.php?f=1&t=1649 [7] with a SSD you can reach 200~400 MB/s rw bandwidth with ~1 ms access time on Sata with a iodrive you can reach 750~1500 MB/s rw bandwidth with ~30 µs access time where an HD you can reach 50~70 MB/s rw bandwidth with 12~25 ms access time on Sata For the 80 GB HD, I defined a 16 GB swap partition and the rest for /tmp. Could be interesting to install also Linux on SSD. Moses ----- Original Message ----- From: Tom Hoar Sent: 04/19/11 03:08 PM To: maria.mach...@ec.europa.eu [8] Subject: Re: [Moses-support] How much Ram for Europarl? Wow. Excellent tip. After looking at pricing on Ebay, it's well-worth the 0-0 investment. We run multiple swap partitions across 4 physical disks, plus a RAID 0 for /tmp space. It speeds things up, but not to your extent. Can you share some details about the drive specs, i.e. interface, cache size, etc? Also, what is your configuration between swap and tmp size? Tom On Mon, 18 Apr 2011 18:01:17 +0200, wrote: > Hello, > > Building the phrase table really used to take me a long, long time. > > I have a 4-processor computer with 8 GB RAM and with a 12 million > segment corpus (about 0.5 billion words EN+PT), the whole training > took about 7 days, of which 2 days to build the phrase table (using > the swap too). > > However, now I have a 80 GB solid-state drive installed for the swap > and temp files and the training of a larger corpus (14 million > segments) took about the same time. The main difference was in the > building of the phrase table: it took only 7 hours. Beautiful! > > I hope this information may be useful to you ... although the corpus > you want to train is not as large. > > Maria José > > -----Original Message----- > From: moses-support-boun...@mit.edu [10] > [mailto:moses-support-boun...@mit.edu [11]] On Behalf Of Tom Hoar > Sent: Monday, April 18, 2011 4:05 PM > To: David Wilkinson > Cc: moses-support@mit.edu [12] > Subject: Re: [Moses-support] How much Ram for Europarl? > > > Your report of 100% physical usage, growing swap usage and low CPU > load > is normal when working with limited RAM machines. With only 4 Gb Ram > and > the new (larger) EuroParl v6 corpus, you could train for 3 or 4 days > depending on how you setup your swap partition. Even then, it's > possible > you will run out of RAM before it's finished. Upgrading to 8 Gb ram > is a > move in the right direction. > > Once it's finished training, you'll want to use the binarized the > tables and language model, which MMM's train-1.11 script creates. > > Tom > > > On Mon, 18 Apr 2011 14:52:10 +0100, Philipp Koehn > > wrote: >> Hi, >> >> I am not familiar with the MMM setup, but one of the causes >> of memory use may be the translation table. You should use >> the on-disk translation table. >> >> -phi >> >> On Mon, Apr 18, 2011 at 2:47 PM, David Wilkinson >> wrote: >>> I have set up an Ubuntu 10.04 system with the >>> moses-for-mere-mortals >>> scripts. The default corpus trained in about 6-7 hours on my system >>> (Athlon >>> x3 3.2Ghz, 4Gb Ram). I am now trying to train the system with the >>> Europarl >>> German-English parallel corpus (about 45m words in each language), >>> again >>> using the default moses-for-mere-mortals settings. The system has >>> been >>> running for 24 hrs and is currently using all the physical memory >>> and about >>> 1.2Gb of swap. None of the cores are being used more than 10%, so >>> like this >>> it will take a very long time to finish. If I double the ram to >>> 8gb, >>> will >>> this be sufficient? >>> Many Thanks >>> David >>> _______________________________________________ >>> Moses-support mailing list >>> Moses-support@mit.edu [15] >>> http://mailman.mit.edu/mailman/listinfo/moses-support [16] >>> >>> >> _______________________________________________ >> Moses-support mailing list >> Moses-support@mit.edu >> http://mailman.mit.edu/mailman/listinfo/moses-support [17] > > _______________________________________________ > Moses-support mailing list > Moses-support@mit.edu > http://mailman.mit.edu/mailman/listinfo/moses-support [18] _______________________________________________ Moses-support mailing list Moses-support@mit.edu http://mailman.mit.edu/mailman/listinfo/moses-support [19] Links: ------ [1] http://en.wikipedia.org/wiki/File:Ddrdrive_x1.jpg [2] http://en.wikipedia.org/wiki/Solid-state_drive [3] http://www.fusionio.com/products/iodrive/ [4] http://www.fusionio.com/products/iodriveduo/ [5] http://www.ocztechnology.com/ocz-revodrive-pci-express-ssd.html [6] http://www.ramsan.com/products [7] http://www.3dnow.net/phpBB2/viewtopic.php?f=1&t=1649 [8] mailto:maria.mach...@ec.europa.eu [9] mailto:maria.mach...@ec.europa.eu [10] mailto:moses-support-boun...@mit.edu [11] mailto:moses-support-boun...@mit.edu [12] mailto:moses-support@mit.edu [13] mailto:pko...@inf.ed.ac.uk [14] mailto:davidzw...@hotmail.com [15] mailto:Moses-support@mit.edu [16] http://mailman.mit.edu/mailman/listinfo/moses-support [17] http://mailman.mit.edu/mailman/listinfo/moses-support [18] http://mailman.mit.edu/mailman/listinfo/moses-support [19] http://mailman.mit.edu/mailman/listinfo/moses-support
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