70-229 and SQL file placement

Discussion in 'MCSE' started by Dale, Jul 24, 2004.

  1. Dale

    Dale Guest

    I'm reading Thomas Moore's book for 70-229. It isn't as full of mistakes as
    most study guides I have read, but some of what he says, I am just not too
    sure about.

    I'd like to get some feedback (arguments) going on SQL Server and file
    placement. Of course, all this discussion should be based on Microsoft's
    perceptions and the exam, which, I would bet money, are way out of step with
    state of the art RAID systems in the real world.

    Moore says that tables that are mostly constant but read a lot should be on
    RAID 5. I think they should be on RAID 1, mirroring. Mirroring allows two
    threads to access the disk mechanics simultaneously. RAID 5, on the other
    hand, is faster for writing because it can drop off a few bytes on one
    drive, then while the mechanics are doing their part, the controller has
    already dropped off bytes to the other drives in the stripe. Do you agree?

    He says that the log files should be on RAID 1 for reliability because they
    are written to often. Well, any RAID except 0 gives data protection in the
    event of a disk failure, but RAID 1 requires 2 writes for each single block
    of data being saved. His reasoning is that calculating parity on a RAID 5
    takes time. I think that calculating parity on a quality hardware RAID
    controller will always be faster (a few hundred processor cycles at most)
    than any hard drive with moving parts could possibly be. What do you think?

    Or more important... what do you think Microsoft thinks?

    Dale Preston
    MCSE, MCDBA, MCAD
    Dale, Jul 24, 2004
    #1
    1. Advertising

  2. Dale

    jwk Guest

    Moore is right; raid 1 is faster than raid 5. raid 1 takes no
    calculation, just simply read and write with cloning the signal to a
    second harddrive. your suggestion that a mirror set could handle two
    threads is not true; al requests are send to both drives. That's why they
    call it mirroring.

    Raid 5 always asks some calculation, no matter how much hardware you use
    for building the raid.every write request takes some calculation.

    If you want good performance on your logs, use raid 0+1; four drives
    forming two pairs of raid 0, mirroring each other.

    my 2p.

    jwk

    "Dale" <> wrote in
    news::

    > I'm reading Thomas Moore's book for 70-229. It isn't as full of
    > mistakes as most study guides I have read, but some of what he says, I
    > am just not too sure about.
    >
    > I'd like to get some feedback (arguments) going on SQL Server and file
    > placement. Of course, all this discussion should be based on
    > Microsoft's perceptions and the exam, which, I would bet money, are
    > way out of step with state of the art RAID systems in the real world.
    >
    > Moore says that tables that are mostly constant but read a lot should
    > be on RAID 5. I think they should be on RAID 1, mirroring. Mirroring
    > allows two threads to access the disk mechanics simultaneously. RAID
    > 5, on the other hand, is faster for writing because it can drop off a
    > few bytes on one drive, then while the mechanics are doing their part,
    > the controller has already dropped off bytes to the other drives in
    > the stripe. Do you agree?
    >
    > He says that the log files should be on RAID 1 for reliability because
    > they are written to often. Well, any RAID except 0 gives data
    > protection in the event of a disk failure, but RAID 1 requires 2
    > writes for each single block of data being saved. His reasoning is
    > that calculating parity on a RAID 5 takes time. I think that
    > calculating parity on a quality hardware RAID controller will always
    > be faster (a few hundred processor cycles at most) than any hard drive
    > with moving parts could possibly be. What do you think?
    >
    > Or more important... what do you think Microsoft thinks?
    >
    > Dale Preston
    > MCSE, MCDBA, MCAD
    >
    >
    >
    jwk, Jul 24, 2004
    #2
    1. Advertising

  3. Dale

    Neil Guest

    babbling on and on again "=?Utf-8?B?Qm9iYnk=?="
    <> spewed in
    news:D:

    > Moore is right in saying that RAID 1 has better write performance but
    > RAID 5 has excellent read performance.


    but the point of an OLTP database would be to write almost as much as you
    read. If you want decent performance in the real world I am still
    sticking with my RAID 0+1 and if I am forced into using a raid 5 system
    it better be for DSS or some crappy little db that no one will notice how
    bad it performs for I,U,D...hardware or software RAID be damned, RAID 0+1
    HW still kicks HW RAID 5's a$$...(and I would like to see you do SW RAID
    0+1 on an MS box <VBEG>)

    --
    Neil MCNGP #30
    Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.

    When I die, I want to die like my grandfather-who died peacefully in
    his sleep. Not screaming like all the passengers in his car.
    Neil, Jul 27, 2004
    #3
  4. >but the point of an OLTP database would be to write almost as much as you
    >read. If you want decent performance in the real world I am still
    >sticking with my RAID 0+1 and if I am forced into using a raid 5 system
    >it better be for DSS or some crappy little db that no one will notice how
    >bad it performs for I,U,D...hardware or software RAID be damned, RAID 0+1
    >HW still kicks HW RAID 5's a$$...(and I would like to see you do SW RAID
    >0+1 on an MS box <VBEG>)


    nah, tera ramsan the way to go!

    Kline Sphere (Chalk) MCNGP #3
    The Poster Formerly Known as Kline Sphere, Jul 27, 2004
    #4
  5. Dale

    Neil Guest

    babbling on and on again The Poster Formerly Known as Kline Sphere <.>
    spewed in news::

    > tera ramsan


    ok, fine. then with conventional disks 0+1 kicks a$$.

    --
    Neil MCNGP #30
    Minutus cantorum, minutus balorum, minutus carborata descendum pantorum.

    When I die, I want to die like my grandfather-who died peacefully in
    his sleep. Not screaming like all the passengers in his car.
    Neil, Jul 27, 2004
    #5
  6. >> tera ramsan
    >
    >ok, fine. then with conventional disks 0+1 kicks a$$.


    touchy, touchy...

    Kline Sphere (Chalk) MCNGP #3
    The Poster Formerly Known as Kline Sphere, Jul 27, 2004
    #6
  7. Dale

    Ken Briscoe Guest

    "Bobby" <> wrote in message
    news:D...

    <snip repost of post that was a post similar to a post made 13 hours ago>

    We get the point, Bobby. Good advice, just too much of it.

    --

    KB - MCNGP "silent thug" #26

    first initial last name AT hotmail DOT com
    Ken Briscoe, Jul 27, 2004
    #7
    1. Advertising

Want to reply to this thread or ask your own question?

It takes just 2 minutes to sign up (and it's free!). Just click the sign up button to choose a username and then you can ask your own questions on the forum.
Similar Threads
  1. TechExams.Net

    free SQL Server Design 70-229 guides

    TechExams.Net, Jul 21, 2003, in forum: MCSD
    Replies:
    1
    Views:
    1,376
    Jamie
    Jul 21, 2003
  2. Tina
    Replies:
    1
    Views:
    505
  3. Cruz Gracia
    Replies:
    1
    Views:
    1,255
  4. phil carpenter
    Replies:
    1
    Views:
    516
    UAError
    Nov 8, 2004
  5. bennido

    70-229 and SQL Server 2005 ...

    bennido, Feb 2, 2005, in forum: MCAD
    Replies:
    2
    Views:
    244
    bennido
    Feb 8, 2005
Loading...

Share This Page