Which is faster /dev/mapper or /dev/cciss?
First I'd like to inform you that I'm not an OS Related I'm an Oracle Applications Database administrator.
Thats why you may see my question is very simple
My Question is:
Which IO type is faster /dev/mapper or /dev/cciss?
I'm asking because while i upgrade an Oracle Applications over Linux Redhat 5 with two iterations (TEST and PROD) i found that the TEST was much more faster than the Production server where the # of processors in production is greater than the TEST Server.
By trubleshooting which task takes a long time, i found the date Insertion is the issue.
and I noticed that the df -h shows the database files resides on /dev/mapper/VolGroupx for PROD
/dev/cciss/c1d0p2 For TEST
So i guess this may be the root cause of that issue, Am i correct?
Is the Mapper Vol. Groups slower than the CCISS?
Also, may i ask you for a document may help me understand the different storage methodologies?