Results 1 to 2 of 2
  1. #1
    Join Date
    Oct 2006
    Location
    CA
    Posts
    210

    Unanswered: RAID 1 or RAID 5 for mdf files?

    I've always heard that RAID 5 (or better, RAID 10) is preferred for the actual database (mdf), but RAID 1 for logging.

    If I have a dedicated physical volume for each, what's the performance hit for selecting RAID 1 for the MDF files? 3%, 20%, 200%?

    Doing so (all RAID1) will allow me to have a separate physical volume for the TEMP database - that is heavily used by my app.

  2. #2
    Join Date
    Oct 2006
    Location
    CA
    Posts
    210

    More info

    I did a search on this forum and found a few threads but nothing zeroing in on a ramification comparison of RAID1 vs. RAID5.

    Found this on Google. It indicates RAID 5 = bad for writes-intensive DB but good for read-only DB like DB-Warehousing.

    We do have a Bill-Of-Material app that does a lot (hundreds of thousands per day) of various flag and quantity updates as well as creating tiny log records, but most other activity is heavily indexed reporting and queries - some reports use temp tables.

    As for DB growth issues, a 140GB volume would hold 10 more years of data with free space to spare.

    In the new 8 bay server I'm considering, I'm thinking 4 RAID-1 volumes:

    Vol1 = OS and all programs
    Vol2 = Log files
    Vol3 = User DB
    Vol4 = System DBs (Master, Temp, etc), OS Swap, and .BAK files.

    I could find a different server with 10 or 12 bays and go RAID 10 or RAID 0+1 for Vol3. Is that worth the trouble/expense? It would be nice to have a hot-spare, as well.
    Last edited by vich; 03-28-08 at 01:54.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •