Re: Why does ASMLib support linux platform only?

At Mon, 14 Apr 2008 20:44:48 -0700 (PDT), Woody Ling wrote:
> I read many articles which said that ASMLib disk can provide better
> performance and easy of management than using RAW devices to form ASM
> disk group. Why does ASMLib support linux platform only if it is
> better? Raw devices are good enough for building ASM disk grouop in
> other platforms such as AIX?

don't know about performance, but i think the main reason for asmlib is/was persistent device naming under linux. in pre 2.6/udev times there was now way to pin down a certain scsi lun to a fixed /dev entry.

for example if you had 3 scsi disks sda, sdb and sdc and you removed sdb, on the subsequent reboot device sdc would become sdb. which is quite a nightmare for the admin.

also with asmlib you do not need to configure raw devices, which makes life even more convenient.

nowadays, with the help of udev and O_DIRECT used by oracle its not strict necessary to use asmlib under linux, imho.

hth
toni

-- 
If you understand what you're doing, you're | toni at stderror dot at
not learning anything.                      | Toni Schmidbauer
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