Hi All, Can we freeze and thaw a zfs file-system either from user land (lockfs for ufs) or from the kernel space or through ioctl? Thanks in advance for your help. Best regards, ajit
ajit jain wrote:> Hi All, > > Can we freeze and thaw a zfs file-system either from user land (lockfs > for ufs) or from the kernel space or through ioctl? >Can you step back a level and explain what you''re trying to achieve? Freezing UFS is to get round ufs-specific issues which don''t apply to ZFS, so you maybe asking the wrong question. -- Andrew
Hi Andrew, I am writing a filtering device which tracks the write to the file-system. I am doing it for ufs, vxfs and for zfs. Sometime for consistent point I need to freeze the file-system which flushes dirty block to the disk and block every IO on the top level. So, for ufs and vxfs I got lockfs and VX_FREEZE/VX_THAW, but with zfs I didn''t get the luck. Thanks for your response. Best regards, ajit On Tue, Jan 27, 2009 at 5:34 PM, Andrew Gabriel <agabriel at opensolaris.org> wrote:> ajit jain wrote: >> >> Hi All, >> >> Can we freeze and thaw a zfs file-system either from user land (lockfs >> for ufs) or from the kernel space or through ioctl? >> > > Can you step back a level and explain what you''re trying to achieve? > > Freezing UFS is to get round ufs-specific issues which don''t apply to ZFS, > so you maybe asking the wrong question. > > -- > Andrew >
ajit jain wrote:> Hi Andrew, > > I am writing a filtering device which tracks the write to the > file-system. I am doing it for ufs, vxfs and for zfs. Sometime for > consistent point I need to freeze the file-system which flushes dirty > block to the disk and block every IO on the top level. So, for ufs and > vxfs I got lockfs and VX_FREEZE/VX_THAW, but with zfs I didn''t get the > luck. >I see no need to freeze the file system, or maybe I would say, I see no benefit to freezing a file system. Perhaps your needs will be met by the snapshot feature which will also cause a sync(2). -- richard> Thanks for your response. > > Best regards, > ajit > > On Tue, Jan 27, 2009 at 5:34 PM, Andrew Gabriel > <agabriel at opensolaris.org> wrote: > >> ajit jain wrote: >> >>> Hi All, >>> >>> Can we freeze and thaw a zfs file-system either from user land (lockfs >>> for ufs) or from the kernel space or through ioctl? >>> >>> >> Can you step back a level and explain what you''re trying to achieve? >> >> Freezing UFS is to get round ufs-specific issues which don''t apply to ZFS, >> so you maybe asking the wrong question. >> >> -- >> Andrew >> >> > _______________________________________________ > zfs-discuss mailing list > zfs-discuss at opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >
On 27 Jan 2009, at 17:59, Richard Elling wrote:> ajit jain wrote: >> Hi Andrew, >> >> I am writing a filtering device which tracks the write to the >> file-system. I am doing it for ufs, vxfs and for zfs. Sometime for >> consistent point I need to freeze the file-system which flushes dirty >> block to the disk and block every IO on the top level. So, for ufs >> and >> vxfs I got lockfs and VX_FREEZE/VX_THAW, but with zfs I didn''t get >> the >> luck. >> > > I see no need to freeze the file system, or maybe I would say, I see > no benefit to freezing a file system. Perhaps your needs will be met > by the snapshot feature which will also cause a sync(2).It sounds like the OP could take advantage of the vscan service <http://www.opensolaris.org/os/project/vscan/ > Cheers, Chris