The answer is fairly straightforward. You can use the definition for Dict Voc if you want since it's typically quite tiny, or just create a new file with say type 2 and seperation of 1 Doesn't matter if there is anything actually in it.
Now from the Universe account where you have this file defined, pop out directly to your system level (Dos or Unix prompt) Do a dir or ls and examine how many BYTES your new file or dict voc consumes. This is your block size. -----Original Message----- From: John Thompson <jthompson...@gmail.com> To: U2 Users List <u2-users@listserver.u2ug.org> Sent: Mon, Nov 28, 2011 2:00 pm Subject: Re: [U2] Question about lvm stipe size - What block size does UV write in? Yeah Red Hat, basically just says take the default. I was just curious if nyone had any other facts on the whole deal when using U2. If you use lvm striping you can specify a chunk/stripe size. If you just se it without any of the mirroring/striping features, there is not hunk/stripe size. Its new hardware, and they are ssd's. There is no hardware RAID, so, the specialists" are recommending LVM instead of RAID because it passes hrough discard/TRIM support. I hate new parts. On Mon, Nov 28, 2011 at 4:53 PM, George Gallen <ggal...@wyanokegroup.com>wrote: > Didn't realize you set a chunk size on an LVM, thought that was a hardware RAID only feature. I would think the chunk size would be dependent on the number of drives in the stripe and The average size of a record in the database. When I setup our RAID array, I went with the default chunk size, but did have the option to Reduce it if I wanted to, but chose not to, since the speed was pretty good (15K SAS drives) George -----Original Message----- From: u2-users-boun...@listserver.u2ug.org [mailto: u2-users-boun...@listserver.u2ug.org] On Behalf Of Wols Lists Sent: Monday, November 28, 2011 4:37 PM To: u2-users@listserver.u2ug.org Subject: Re: [U2] Question about lvm stipe size - What block size does UV write in? On 28/11/11 18:15, John Thompson wrote: > So I'm setting up a lvm striping plus mirrorring configuration with 4 disks > to use for a Universe database in Linux. > > And I'm curious, what block size does UV write in? > > Is it 4k blocks? Less or more than that? By default, iirc, it's 4K. INFORMATION was 2K. But why should that matter as far as your RAID is concerned? > > As far as lvm or raid, what stripe sizes are your RAID arrays or LVM > volumes set to? 64k? And what size does your DISKS have their buffers set to? I think the modern default is 4 *meg*. > > Our current machine is set to 64K, but, I was just curious if there is some > recommended size to use. > I am referring to a stripe size in a RAID array or lvm logical volume. > Can't give you any advice, unfortunately, other than to say it's complicated, and you probably need a specialist. If you're running licenced RHEL, I'd get Red Hat to advise. My instinct would be to go for whatever the disk buffers are, but I think that's the wrong choice... Cheers, Wol _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users -- ohn Thompson ______________________________________________ 2-Users mailing list 2-us...@listserver.u2ug.org ttp://listserver.u2ug.org/mailman/listinfo/u2-users _______________________________________________ U2-Users mailing list U2-Users@listserver.u2ug.org http://listserver.u2ug.org/mailman/listinfo/u2-users
