Joe, thanks for the feedback. The bonnie results were not actually mine, I was just pointing to some numbers run by Paul Moen.
Your 1GB file data is likely more representative, but with 15 GB ram, > you need to be testing 30-60 GB files. > I'll try to tweak the BPS bonnie tests to run some large files... On Fri, Mar 7, 2008 at 11:57 AM, Joe Landman < [EMAIL PROTECTED]> wrote: > Peter Skomoroch wrote: > > > Extra Large Instance: > > > > 15 GB memory > > 8 EC2 Compute Units (4 virtual cores with 2 EC2 Compute Units > each) > > 1,690 GB instance storage (4 x 420 GB plus 10 GB root partition) > > 64-bit platform > > I/O Performance: High > > Note: minor criticism, but overall, nice results. > > Looking over your bonnie results is worth a quick comment. Any time you > have bonnie or IOzone (or other IO benchmarks) which are testing file > sizes less than ram size, you are not actually measuring disk IO. This > is cache speed pure and simple. Either page/buffer cache, or RAID > cache, or whatever. > > We have had people tell us to our face that their 2GB file results (on a > 16 GB RAM machine) were somehow indicative of real file performance, > when, if they walked over to the units they were testing, they would > have noticed the HD lights simply not blinking ... Yeah, an amusing > beer story (the longer version of it), but a problem none-the-less. > > Your 1GB file data is likely more representative, but with 15 GB ram, > you need to be testing 30-60 GB files. > > Not trying to be a marketing guy here or anything like that ... we test > our JackRabbit units with 80GB to 1.3TB sized files. We see (sustained) > 750 MB/s - 1.3 GB/s in these tests. We also note some serious issues > with the linux buffer cache and multiple RAID controllers (buffer cache > appears to serialize access). We do this as we actually want to measure > disk performance, and not buffer cache performance. > > That criticism aside, nice results. It shows what a "cloud" can do. > > > Price: $0.80 per instance hour > > > -- > Joseph Landman, Ph.D > Founder and CEO > Scalable Informatics LLC, > email: [EMAIL PROTECTED] > web : http://www.scalableinformatics.com > http://jackrabbit.scalableinformatics.com > phone: +1 734 786 8423 > fax : +1 866 888 3112 > cell : +1 734 612 4615 > -- Peter N. Skomoroch [EMAIL PROTECTED] http://www.datawrangling.com
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