RE: SSD on temp or undo tablespace

From: Sheehan, Jeremy <>
Date: Wed, 23 May 2012 13:01:45 -0400
Message-ID: <>

We use SSD on 2 databases and they're for heavy read/write tablespaces and one specific temp tablespace (primary application temp space). I can say for sure that we've seen improvements with the heavy writes. Temp, tho.... ?


-----Original Message-----

From: [] On Behalf Of Rui Cat Sent: Wednesday, May 23, 2012 12:29 PM
To:; oracle-l
Subject: Re: SSD on temp or undo tablespace

Personally I would not suggest putting heavy write tablespaces on SSD's since they do have a write limit to them. Some are better than others of course but there is still a write limit to them and it's the firmware that controls the "wear-leveling" of the drive. So if your firmware goes so does your drive. We played with Fusion IO cards and their recommendation was to hold back 20% of the card for block write wear (once a block can no longer be written to the firmware will use another block from the reserve and move the data to the new block) which is a big loss of storage when you are looking at things like 600 gig cards. Their estimated life cycle for heavy IO apps was 18 months.  The goods news is that they are fast. 

I am not sure that that is enough to warrant putting those tablespaces on SSD's.

my 2 cents.


 From: qihua wu <> To: oracle-l <> Sent: Monday, May 21, 2012 7:57:39 PM
Subject: SSD on temp or undo tablespace  

Hi experts,
We have limited budget, and put SSD for both undo and temp tablespace. We encountered ora-01555 error and some error that temp tablespace is not enough. I just want to know how SSD will be helpful for undo and temp tablespace. If temp on SSD has only limited benefit, we might assign all the SSD disk to undo, then use normal hard disk to temp. Did anyone have some suggestions


-- Received on Wed May 23 2012 - 12:01:45 CDT

Original text of this message