72f53c5694
This reverts commit 9dcb97198338ba2d8764dd5604b278118612f74 which was originally introduced to debug occasional slow I/Os. These I/Os would complete eventually but were observed to take several 100 seconds. The root cause of this issue was the CFQ scheduler which can, under certain conditions, excessively delay an I/O from being issued to the device. This issue was mitigated somewhat by commit 84daaddedbfc9cf4bd1490d8a6f4b2967051e308 which ensures the I/O elevator gets changed even for DM style devices. This change isn't in any way harmful but it does conflict with a required change to properly account from I/O wait time. Because Linux does not export the io_schedule_timeout() function we must instead rely on io_schedule() via cv_wait_io(). The additional debugging information which was added to the delay event has been intentionally left in place. Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
Native ZFS for Linux! ZFS is an advanced file system and volume manager which was originally developed for Solaris. It has been successfully ported to FreeBSD and now there is a functional Linux ZFS kernel port too. The port currently includes a fully functional and stable SPA, DMU, and ZVOL with a ZFS Posix Layer (ZPL) on the way!
$ ./configure
$ make pkg
To copy the kernel code inside your kernel source tree for builtin compilation:
$ ./configure --enable-linux-builtin --with-linux=/usr/src/linux-...
$ ./copy-builtin /usr/src/linux-...
Full documentation for building, configuring, and using ZFS can be found at: http://zfsonlinux.org