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* core: GFID filehandle based backend and anonymous FDsAnand Avati2012-01-201-1/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1. What -------- This change introduces an infrastructure change in the filesystem which lets filesystem operation address objects (inodes) just by its GFID. Thus far GFID has been a unique identifier of a user-visible inode. But in terms of addressability the only mechanism thus far has been the backend filesystem path, which could be derived from the GFID only if it was cached in the inode table along with the entire set of dentry ancestry leading up to the root. This change essentially decouples addressability from the namespace. It is no more necessary to be aware of the parent directory to address a file or directory. 2. Why ------- The biggest use case for such a feature is NFS for generating persistent filehandles. So far the technique for generating filehandles in NFS has been to encode path components so that the appropriate inode_t can be repopulated into the inode table by means of a recursive lookup of each component top-down. Another use case is the ability to perform more intelligent self-healing and rebalancing of inodes with hardlinks and also to detect renames. A derived feature from GFID filehandles is anonymous FDs. An anonymous FD is an internal USABLE "fd_t" which does not map to a user opened file descriptor or to an internal ->open()'d fd. The ability to address a file by the GFID eliminates the need to have a persistent ->open()'d fd for the purpose of avoiding the namespace. This improves NFS read/write performance significantly eliminating open/close calls and also fixes some of today's limitations (like keeping an FD open longer than necessary resulting in disk space leakage) 3. How ------- At each storage/posix translator level, every file is hardlinked inside a hidden .glusterfs directory (under the top level export) with the name as the ascii-encoded standard UUID format string. For reasons of performance and scalability there is a two-tier classification of those hardlinks under directories with the initial parts of the UUID string as the directory names. For directories (which cannot be hardlinked), the approach is to use a symlink which dereferences the parent GFID path along with basename of the directory. The parent GFID dereference will in turn be a dereference of the grandparent with the parent's basename, and so on recursively up to the root export. 4. Development --------------- 4a. To leverage the ability to address an inode by its GFID, the technique is to perform a "nameless lookup". This means, to populate a loc_t structure as: loc_t { pargfid: NULL parent: NULL name: NULL path: NULL gfid: GFID to be looked up [out parameter] inode: inode_new () result [in parameter] } and performing such lookup will return in its callback an inode_t populated with the right contexts and a struct iatt which can be used to perform an inode_link () on the inode (without a parent and basename). The inode will now be hashed and linked in the inode table and findable via inode_find(). A fundamental change moving forward is that the primary fields in a loc_t structure are now going to be (pargfid, name) and (gfid) depending on the kind of FOP. So far path had been the primary field for operations. The remaining fields only serve as hints/helpers. 4b. If read/write is to be performed on an inode_t, the approach so far has been to: fd_create(), STACK_WIND(open, fd), fd_bind (in callback) and then perform STACK_WIND(read, fd) etc. With anonymous fds now you can do fd_anonymous (inode), STACK_WIND (read, fd). This results in great boost in performance in the inbuilt NFS server. 5. Misc ------- The inode_ctx_put[2] has been renamed to inode_ctx_set[2] to be consistent with the rest of the codebase. Change-Id: Ie4629edf6bd32a595f4d7f01e90c0a01f16fb12f BUG: 781318 Reviewed-on: http://review.gluster.com/669 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Anand Avati <avati@gluster.com>
* Change Copyright current yearPranith Kumar K2011-08-101-1/+1
| | | | | | | | Change-Id: I2d10f2be44f518f496427f257988f1858e888084 BUG: 3348 Reviewed-on: http://review.gluster.com/200 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Anand Avati <avati@gluster.com>
* LICENSE: s/GNU Affero General Public/GNU General Public/Pranith Kumar K2011-08-061-3/+3
| | | | | | | | Change-Id: I3914467611e573cccee0d22df93920cf1b2eb79f BUG: 3348 Reviewed-on: http://review.gluster.com/182 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Anand Avati <avati@gluster.com>
* nfs: opendir/closedir for every readdirAnand Avati2010-11-151-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Revert "nfs3: Unref & unbind dir fd with inode lock on EOF" This reverts commit 4e6fb304ce41acbaf7c9ba67c06bf443e65082e8. The above commit (which unbinds fds at EOF) does not fix the original bug (1619) because a readdir from a second app could have already started before the readdir_cbk of the first app's readdir reaches NFS code. Hence the race still exists. Performing extra unrefs when EOF is received is not a reliable way of detecting that a client has performed a closedir (and to close the fd ourselves). Neither is interpreting a 0 cookies a new opendir. Clients can always use telldir/seekdir and hit EOFs twice. Due to the way NFS3 protocol is designed, it is just not possible for the server to reliably detect opendirs/closedirs performed by the client and map the corresponding readdirs to the same dir fd on the server side. The only reliable way of fixing this is to perform opendir/closedir at the cost of performance. Any optimization towards keeping dir fds open attempting to map them with application's opendir/closedir will either result in fd leaks or extra fd unrefs. Signed-off-by: Anand V. Avati <avati@blackhole.gluster.com> Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 2061 (NFS server crashes in readdir_fstat_cbk due to extra fd unref) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=2061
* fuse: retire the faked-FLUSH-upon-RELEASE hackCsaba Henk2010-10-261-1/+0
| | | | | | | | | | | | | | | | | | Now the code has lived up to the glorious state of not relying on getting the FLUSH whenever a file is released. So we don't need to forge one in release for the cases when the kernel doesn't send it. Undo commits: - 155ffe5c - c50bc710 - b8779318 (partly, just release related parts) Signed-off-by: Csaba Henk <csaba@gluster.com> Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 223 (flush not sent) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=223
* Copyright changesVijay Bellur2010-10-111-1/+1
| | | | | | | | Signed-off-by: Vijay Bellur <vijay@gluster.com> Signed-off-by: Vijay Bellur <vijay@dev.gluster.com> BUG: 971 (dynamic volume management) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=971
* Change GNU GPL to GNU AGPLPranith K2010-10-041-3/+3
| | | | | | | | Signed-off-by: Pranith Kumar K <pranithk@gluster.com> Signed-off-by: Vijay Bellur <vijay@dev.gluster.com> BUG: 1388 () URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1388
* nfs3: Unref & unbind dir fd with inode lock on EOFv3.1.0qa26Shehjar Tikoo2010-09-171-0/+2
| | | | | | | | | | | | | | ..so that when EOF is reached on this fd, any further requests on the same inode do not get handled through this fd but result in a new fd being opened. Unbinding results in the fd getting deleted from the inode's fd list. Signed-off-by: Shehjar Tikoo <shehjart@gluster.com> Signed-off-by: Vijay Bellur <vijay@dev.gluster.com> BUG: 1619 (glusterfs nfs server crashed on dht+replica(2x2)) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1619
* performance/write-behind: dump contents of wb-fileRaghavendra G2010-09-161-0/+5
| | | | | | | | Signed-off-by: Raghavendra G <raghavendra@gluster.com> Signed-off-by: Vijay Bellur <vijay@dev.gluster.com> BUG: 1059 (enhancements for getting statistics from performance translators) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1059
* fuse resolve related changesAmar Tumballi2010-08-111-2/+9
| | | | | | | | | | | | | Now fuse is fully complaint with DVM, as even if there is a fop request on inode belonging to old graph, it will be resolved corresponding to new graph and operations will be performed wrt. new graph, which makes DVM truely spontaneous. Signed-off-by: Amar Tumballi <amar@gluster.com> Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 1240 (DVM: after graph change, inodes should resolve to new inode-table) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=1240
* dynamic volume changes for graph replacementAnand Avati2010-06-071-9/+32
| | | | | | | | Signed-off-by: Anand V. Avati <avati@blackhole.gluster.com> Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 971 (dynamic volume management) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=971
* Changed occurrences of Z Research to Gluster.Vijay Bellur2009-10-071-1/+1
| | | | Signed-off-by: Anand V. Avati <avati@dev.gluster.com>
* fuse: emit a flush from release if we didn't get an adjacent FLUSH message ↵Csaba Henk2009-09-231-0/+1
| | | | | | | | | from the kernel Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 223 (flush not sent) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=223
* cleanup 'ctx' from inode and fdAmar Tumballi2009-07-161-1/+0
| | | | | | | | | Removing unused 'dict_t *ctx' from both inode and fd structures. Signed-off-by: Anand V. Avati <avati@dev.gluster.com> BUG: 128 (cleanup unwanted ctx dictionary in 'inode' and 'fd' structures.) URL: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=128
* booster: Remove gf_fd_unused_get2Shehjar Tikoo2009-06-291-3/+4
| | | | Signed-off-by: Anand V. Avati <avati@dev.gluster.com>
* libglusterfs: Change GF_FDENTRY_ALLOCATED constantShehjar Tikoo2009-06-181-3/+2
| | | | | | | | | This change is being brought in so that we can differentiate between fdentry_ts when debugging using gdb. Signed-off-by: Anand V. Avati <avati@dev.gluster.com>
* libglusterfs: Turn fd-table O(1)Shehjar Tikoo2009-06-151-2/+18
| | | | | | | | | This commit reduces CPU usage of gf_fd_unused_get drastically by making it O(1) instead of O(n). Related to: http://bugs.gluster.com/cgi-bin/bugzilla3/show_bug.cgi?id=16 Signed-off-by: Anand V. Avati <avati@dev.gluster.com>
* Add lock-less versions of fd_ctx_*Vikas Gorur2009-04-071-0/+9
| | | | | | | | Added __fd_ctx_get __fd_ctx_set __fd_ctx_del which do not hold any lock. Signed-off-by: Anand V. Avati <avati@amp.gluster.com>
* server-protocol - reimplement connection cleanup to happen in 2 phasesRaghavendra G2009-04-031-0/+3
| | | | | | | | | | | - first phase, which happens when POLLERR is received on transport, releases all locks, flushes all open fds. - second phase, which happens when both the transports of connection destroyed, destroys the containers like lock table, fd table along with the connection. - the first phase, clears up any references to transport held by translators like posix-locks(in the form of blocked locks) paving way for the second phase. Signed-off-by: Anand V. Avati <avati@amp.gluster.com>
* updated copyright header to extend copyright upto 2009Basavanagowda Kanur2009-02-261-1/+1
| | | | | | updated copyright header to include 2009. Signed-off-by: Anand V. Avati <avati@amp.gluster.com>
* fd->lock added to protect transactions for accessing and modifying fd->_ctx.Basavanagowda Kanur2009-02-261-0/+3
| | | | | | fd->_ctx access and modifications are now protected by fd->lock. Signed-off-by: Anand V. Avati <avati@amp.gluster.com>
* Added all filesVikas Gorur2009-02-181-0/+107
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