On Tue, Dec 14, 2010 at 8:52 AM, Gary Dusbabek <gdusba...@gmail.com> wrote: > On Tue, Dec 7, 2010 at 20:25, Edward Capriolo <edlinuxg...@gmail.com> wrote: >> I am quite ready to be stoned for this thread but I have been thinking >> about this for a while and I just wanted to bounce these ideas of some >> guru's. >> >> ... >> >> The upsides ? >> 1) Since disk/instance failure only degrades the overall performance >> 1/6th (RAID0 you lost the entire node) (RAID5 still takes a hit when >> down a disk) >> 2) Moves and joins have less work to do >> 3) Can scale up a single node by adding a single disk to an existing >> system (assuming the ram and cpu is light) >> 4) OPP would be "easier" to balance out hot spots (maybe not on this >> one in not an OPP) >> > > Sorry for chiming in so late, but another benefit is that it amortizes > stop-the-world garbage collection across 6 jvms. > >> What does everyone thing? Does it ever make sense to run this way? >> > > I think it would be a great way of utilizing CPU and memory, assuming > you can come up with the IO bandwidth. > > Gary. >
The biggest deal I see is SSTables, bloom filters, and indexes are less efficient with 4x 10GB entities verses 1x 40 GB entity . On the flip side of this, 6x independent disks will be able to seek faster then a RAID0 disk (because of queuing on the raid0). This might be a big win since a person with more data then memory is doing much more seeking. Also a cool flip side about a "micrandra" would be taking a hot swap disk between nodes, this would give you a blade server like effect, again much more flexibility then a big RAID set. (and of course a blade server would provide this functionality :)
