some questions regarding ssds

xout
2009-11-22
2013-04-27
  • xout
    xout
    2009-11-22

    hello everybody,

    first of all i'd like to explain a bit of my background why i'm asking in the discussion section of hdparm/wiper.sh. a couple of days ago i received my rma'd intel x25-m g2 postville 80G ssd, which was bricked after installing the 02ha firmware update coming along with trim enabled. the current drive uses the old firmware, not ready for trim yet. intel told me there should be a new update in about two weeks (eta).
    therefore some things came into my mind, i'd like to question at the "centerstage" of hdparm. i already informed myself about ssds in several forums and articles (e.g. anandtech ssd anthology) but nevertheless some things are not quite clear for me.
    opinions in forums differ a lot…


    here is some information about my system:

    - usage htpc
    - nvidia ion / atom 330
    - 4G ram
    - intel x25-m g2 postville 80G -> ahci
    - Linux version 2.6.31-gentoo-r6 / (gcc version 4.3.4 (Gentoo 4.3.4
       p1.0, pie-10.1.5) ) #3 SMP PREEMPT / 32bit
    - hdparm-9.27
    - ext2 on boot
    - ext4 on /
    - ext4 on /mnt/media
    - no wm/de, just xbmc on top of xorg


    current kernels do not support the ata trim command, mark lord posted a statement in the ocz forums. at the moment the choice to trim ssds on linux is to use the wiper.sh script, right? as far as i know wiper.sh does not come along bundled with hdparm, right?
    since gentoo is pretty write intensive in some directories i planned originally to outsource some of them to a magnetically drive to save the ssd a bit, but i'm not sure whether this is really necessary or not. these are:


    - /tmp
    - /usr/portage
    - /usr/src
    - /var
    - /home/user/.mediacenterdatabase
    - (/mnt/media)
    - (/mnt/backup)


    that said here are the first things that came into my mind:

    general:

    - alignment of ssds: can anyone recommend a good information source 
       or tutorial? i found several but these differ in their statements.
    - intel recommends to leave 10-20% of the ssd unpartitioned. true or false? or does this only apply in case the ssd isn't trim enabled yet?
    - would you recommend to go for a 32bit or 64bit operating system. some people reported better performance on a 64bit system.
    - suppress fsck at boottime or not? people's opinions differ at this
       point, too.
    - should i set "noatime" AND "noadir" in stab or is only "noatime" just
       fine?
    - wait for new firmware or just go ahead?


    case1 => no trim enabled firmware:

    - should i outsource write intensive directories to a magnetical drive?
    - if not outsourced, would wiper.sh do the job if there is no trim enabled firmware?
    - any special settings in the kernel for ext4?


    case2 => trim enabled firmware:

    - should i outsource write intensive directories to a magnetical drive?
    - if not outsourced, would wiper.sh do the job if there is trim enabled
       firmware?
    - any special settings in the kernel for ext4?


    that's it for now. i hope some of you could help me with these questions. :) if you have any other proposals, then just let me know please.

    best regards,
    xout