[OpenAFS] Solaris 10u6: ZFS cache?
Derrick Brashear
shadow@gmail.com
Tue, 11 Nov 2008 18:03:32 -0500
>>> o The ois_DisableAtime routine was trying to update
>>> the inode. I skipped that part of the code. Is this
>>> OK or not? Is there another way to update the flag?
>>
>
> What is this code trying to do? Is it trying to say don't
> update the atime of the cache file as this improves performance?
That's the goal. The atime on cache inodes is meaningless. They aren't
real files.
>> Perhaps we should use values just shy of 0xffffffff.
>
> Yes that would work.
>
> It also looks like ZFS is storing the object ID as the
> inode which can be obtained from a stat() with -D_FILE_OFFSET_BITS=64
Can we leverage that? Actually, if we do, we have the issue that we
can no longer use tmpfs as cache, which I assume with your first patch
we can.
> And it looks like the vnode associated with an object can be obtained
> via a vfs_vget(vfs, vnode **, fid)
> The fid can have the object ID.
>
> So it looks like if there was a ZfsSOpen much like there is a
> XvfsOpen, if could get constructe an fid, and called VFS_VGET
> to get the vnode. In this case then the AFS_CACHE_VNODE_PATH
> would not be needed.
Ok.
Derrick