[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: SATA problems



Rohan Kulkarni wrote:
Hello,
So will it help if I have a faster processor or I add in more RAM to my system?

On 7/3/07, *John Wendel* < john wendel metnet navy mil <mailto:john wendel metnet navy mil>> wrote:

    Rohan Kulkarni wrote:
     >
     >
     > On 7/3/07, *Rohan Kulkarni* < rohan ak1 gmail com
    <mailto:rohan ak1 gmail com>
     > <mailto:rohan ak1 gmail com <mailto:rohan ak1 gmail com>>> wrote:
     >
     >
     >
     >     On 7/2/07, *John Wendel* < john wendel metnet navy mil
    <mailto:john wendel metnet navy mil>
     >     <mailto:john wendel metnet navy mil
    <mailto:john wendel metnet navy mil>>> wrote:
     >
     >         Rohan Kulkarni wrote:
     >         >
     >         >
     >         >  On 7/2/07, *Tim* <ignored_mailbox yahoo com au
    <mailto:ignored_mailbox yahoo com au>
     >         <mailto: ignored_mailbox yahoo com au
    <mailto:ignored_mailbox yahoo com au>>
     >         >  <mailto:ignored_mailbox yahoo com au
    <mailto:ignored_mailbox yahoo com au>
     >         <mailto: ignored_mailbox yahoo com au
    <mailto:ignored_mailbox yahoo com au>>>> wrote:
     >         >
     >         >     On Mon, 2007-07-02 at 19:14 +0530, Rohan Kulkarni
    wrote:
     >         >      > My motherboard supports hard disk speed of
    150MB/s but i
     >         get only
     >         >      > 15MB/s speed
     >         >
     >         >     Have you double-checked that the figures you're
    reading at
     >         are bits per
     >         >     second or bytes per second?
     >         >
     >         >     --
     >         >     (This box runs FC5, my others run FC4 & FC6, in
    case that's
     >         >     important to the thread.)
     >         >
     >         >     Don't send private replies to my address, the
    mailbox is
     >         ignored.
     >         >     I read messages from the public lists.
     >         >
     >         >
     >         >
     >         >  Hello,
     >         >            Yes I have checked with the motherboard
     >         specifications.It
     >         >  says that it supports
     >         >            a speed of 150MB/s.It is bytes for
    second.Though my
     >         hard disk
     >         >  supports native command queing my motherboard does not
    support
     >         it.
     >         >
     >         >     --
     >         >     fedora-list mailing list
     >         >     fedora-list redhat com
    <mailto:fedora-list redhat com> <mailto: fedora-list redhat com
    <mailto:fedora-list redhat com>>
     >         <mailto: fedora-list redhat com
    <mailto:fedora-list redhat com> <mailto:fedora-list redhat com
    <mailto:fedora-list redhat com>>>
     >         >     To unsubscribe:
     >         https://www.redhat.com/mailman/listinfo/fedora-list
     >         >     < https://www.redhat.com/mailman/listinfo/fedora-list>
     >         >
     >         >
     >
     >         It doesn't matter what speed your motherboard (SATA
    controller)
     >         supports if the disk speed is slower. What brand/model of
    disk
     >         do you
     >         have? What kernel version? How are you measuring the disk
    speed?
     >
     >         Regards,
     >
     >         John
     >
     >
     >
     >     Hello,
     >              I have a Seagate ST3160211AS.It is a Barracuda 160GB
    hard
     >     disk with a
     >              speed of 7200RPM.It supports upto 300MB/s with Native
     >     Command Queing.I checked the average  speed of copying by
    copying a
     >              3GB file from one FAT32 partition to another.I got a
     >     average speed of around
     >              15MB/s.I have the kernel 2.6.21-1.3228.fc7
     >                                                              Thanks...

     >
     >
     >
     >       Can anyone please help me...do i need to update to the latest
     > kernel??or do i need
     >       to download some drivers.
     >
     >         --
     >         fedora-list mailing list
     >         fedora-list redhat com <mailto:fedora-list redhat com>
    <mailto:fedora-list redhat com <mailto:fedora-list redhat com>>
     >         To unsubscribe:
     >         https://www.redhat.com/mailman/listinfo/fedora-list
     >         <https://www.redhat.com/mailman/listinfo/fedora-list>
     >
     >
     >

    You don't really have a problem!

    Don't confuse the maximum interface transfer speed (150 MB/s) with
    your disk transfer speed (approx 40-50 MB/s).

    When you copy a file, you read the old file, and then you write the
    new file, rinse and repeat until done. So your transfer speed is going
    to be approximately 1/2 to disk speed. And now you need to add in the
    operating system overhead, allocating blocks for the new file, and all
    the seek time, moving the disk heads between the old file blocks and
    the new file blocks.

    15 MB/s seems reasonable. On my box, using a single drive, I get a
    write speed of 30 MB/s for a 3 GB file and a copy speed of 14 MB/s.

    Need more speed, get more disks and a raid controller.

    Regards,

    John

Faster processor can help lots of things, but not disk speed. More memory (usually) helps, the kernel can use it for disk cache if nothing else.

Anybody else out there got any advice for speeding up SATA drives ?

Regards,

John




[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]