** Description changed:

- Tried installing Maverick alpha 2 ( alternate-i386) - because its an
- eeepc 901 i created a usb install disk with the usb creator. My eeepc
- has 2 ssd drives, 4GB and 8GB - On the 4GB one i created a 300mb ext2
- partition for  /boot, and the rest of the space btrfs for / . The 8GB
- drive was all btrfs. Partitioning was quick and painless but install was
- much too slow. After 2.5 hours i stopped the install because i had only
- reached 34% - this is not right. Lucid + ext4 on the same hardware is
- very fast. I know btrfs is experimental but i have my mythbuntu system
- with a 1.5TB storage disk formated to btrfs and its quick. Does it have
- something todo with aligning blocks / partitions?
+ Installation and upgrades on btrfs are *extremely* slow.  This is
+ because dpkg makes extensive fsync() calls to make sure that a power
+ loss in the middle of an operation does not leave the system in a broken
+ state.  These calls have a significant performance penalty on other
+ filesystems ( such as ext[234] ), but on btrfs, the penalty is multiple
+ orders of magnitude.
+ 
+ As a workaround, you can use the eatmydata package/command around dpkg
+ /apt-get to disable the fsync() calls and restore good performance
+ during upgrades, at the risk of hosing the system if it crashes.  The
+ apt-btrfs-snapshot package will have apt make a snapshot before it
+ begins an upgrade so that if things do go wrong, you can at least roll
+ back to the snapshot.

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https://bugs.launchpad.net/bugs/601299

Title:
  btrfs fsync() is extremely slow

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