Re: Raw Disk still preferred for 11.5?

Hello Fernando, first of all thanks for the explanation; sounds too good to be true (wollmilchsau which is an animal who delivers milk wool and meat....) ; when i have to setup new stuff i will sure test it.. > I didn't test this recently, but I recall a situation on Tru64 using advfs hmm on windhowze restores failed because of allocations; the answer was retry and before one did make sure the files were there with the appropiate size. The file alloc was not really what i meant; even using block mode raw devs is much slower on sun a factor 2 to 3 is not uncommon; in the past it was worse; it could lock up a machine until the restore was completed. simply try a restore. > > > Also on aix i could do 50 mb/sec writes to char mode raw (yeah yeah 7 > > years ago...) while the aix teacher did 40 mb/sec writing to the > > filesystem using dd.....and that was really the best he could do.... > > Using the same block size? Nope the aix teacher could choose the best size he wanted/needed; i did checkpoint writes so 16 pages/io (64 kb) and made damn sure i did 16 pages ordered... filesystem was striped across 10 disks or so i used 10 disks for dbspaces no striping and i hit them all hard when i wrote stuff. > Now the complex stuff...: > What DIRECT_IO does really depends on your file system supported features. hmm hope it is not only reiserfs on linux which supports this; have some really bad experiences with that one will have a look when the time is there. Superboer.