Everything I have read has definitely recommended putting the redo logs on
SSD. I even wrote an article on the subject several years ago.
On Wed, Dec 16, 2015 at 8:54 AM, Storey, Robert (DCSO) <
RStorey@xxxxxxxxxxxxxxxxxx> wrote:
Morning,
I’ve been reading multiple docs on SSD/HDD and the benefits within an
oracle database.
If I am reading this write, for an OLTP system, the SSD/FLASH will provide
excellent random read/write abilities.
But folks seem contradicted on using the SSD for the Redo logs. Some say
its best practice, others say it does not buy you anything.
I have a 24/7 OLTP application that generates a modest amount of redo. My
overall DB is about 95 gigs, I generate about 600megs of redo in a day
(10meg files, switching every 30 or so). My system is getting to end of
life, and I see more log_file_sync waits, and buffer busy waits. I suspect
my I/O subsystems are getting worked hard. My top waits appear to be
sequent file reads and scattered reads, log file sync, and buffer busy.
What’s the general verdict on using SSD for the data files? Best idea
for redos? My thoughts there are separating them to different drives, ie,
two separate single disks, with a group member on each disk.
Thoughts?
Thanks
