Hi Guy, On Mon, 2005-04-04 at 02:08, Guy wrote: > I am top posting since I am starting a new topic. > > Don't get me wrong, I like and trust md, at least with kernel 2.4. > > This is the first I knew about EVMS, the website makes it sound wonderfull! > http://evms.sourceforge.net/ > > Is EVMS "better" than md? > Is EVMS replacing md? > Any performance data comparing the 2? EVMS uses MD and Device Mapper (DM). So, EVMS does not replace MD. For RAID-1 & RAID-5, EVMS ioctl md driver to start the array. For MD's RAID-0 and LINEAR arrays, EVMS uses DM stripe and linear targets to create device nodes. You can say EVMS replaces mdadm (sorry, NeilB :)) Regarding performance issue (raid1 & raid5), I/O requests from MD will appear on DM's queue. So, it is probably slower. How much slower, we never run any benchmark to find out. > > One bad point for EVMS, no RAID6. :( We (EVMS team) intended to support RAID6 last year. But as we all remember RAID6 was not stable then. I may write a plugin to support RAID6 soon. > One good point for EVMS, bad Block Relocation (but only on writes). > Not sure how EVMS handles read errors. As I mentioned above, kernel MD driver handle I/O requests for raid1 and raid5. > > I am getting on the mailing list(s). I must know more about this!!! > Welcome aboard :) -- Regards, Mike T. - 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
