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2014-09-29Merge branch 'jk/index-pack-threading-races' into maintLibravatar Junio C Hamano1-2/+31
When receiving an invalid pack stream that records the same object twice, multiple threads got confused due to a race. * jk/index-pack-threading-races: index-pack: fix race condition with duplicate bases
2014-08-29index-pack: fix race condition with duplicate basesLibravatar Jeff King1-2/+31
When we are resolving deltas in an indexed pack, we do it by first selecting a potential base (either one stored in full in the pack, or one created by resolving another delta), and then resolving any deltas that use that base. When we resolve a particular delta, we flip its "real_type" field from OBJ_{REF,OFS}_DELTA to whatever the real type is. We assume that traversing the objects this way will visit each delta only once. This is correct for most packs; we visit the delta only when we process its base, and each object (and thus each base) appears only once. However, if a base object appears multiple times in the pack, we will try to resolve any deltas based on it once for each instance. We can detect this case by noting that a delta we are about to resolve has already had its real_type field flipped, and we already do so with an assert(). However, if multiple threads are in use, we may race with another thread on comparing and flipping the field. We need to synchronize the access. The right mechanism for doing this is a compare-and-swap (we atomically "claim" the delta for our own and find out whether our claim was successful). We can implement this in C by using a pthread mutex to protect the operation. This is not the fastest way of doing a compare-and-swap; many processors provide instructions for this, and gcc and other compilers provide builtins to access them. However, some experiments showed that lock contention does not cause a significant slowdown here. Adding c-a-s support for many compilers would increase the maintenance burden (and we would still end up including the pthread version as a fallback). Note that we only need to touch the OBJ_REF_DELTA codepath here. An OBJ_OFS_DELTA object points to its base using an offset, and therefore has only one base, even if another copy of that base object appears in the pack (we do still touch it briefly because the setting of real_type is factored out of resolve_data). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-21Merge branch 'maint'Libravatar Junio C Hamano1-2/+1
* maint: use xmemdupz() to allocate copies of strings given by start and length use xcalloc() to allocate zero-initialized memory
2014-07-21use xcalloc() to allocate zero-initialized memoryLibravatar René Scharfe1-2/+1
Use xcalloc() instead of xmalloc() followed by memset() to allocate and zero out memory because it's shorter and avoids duplicating the function parameters. Signed-off-by: Rene Scharfe <l.s.r@web.de> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-07-16Merge branch 'jk/strip-suffix'Libravatar Junio C Hamano1-15/+14
* jk/strip-suffix: prepare_packed_git_one: refactor duplicate-pack check verify-pack: use strbuf_strip_suffix strbuf: implement strbuf_strip_suffix index-pack: use strip_suffix to avoid magic numbers use strip_suffix instead of ends_with in simple cases replace has_extension with ends_with implement ends_with via strip_suffix add strip_suffix function sha1_file: replace PATH_MAX buffer with strbuf in prepare_packed_git_one()
2014-07-16Merge branch 'jk/commit-buffer-length' into maintLibravatar Junio C Hamano1-1/+2
A handful of code paths had to read the commit object more than once when showing header fields that are usually not parsed. The internal data structure to keep track of the contents of the commit object has been updated to reduce the need for this double-reading, and to allow the caller find the length of the object. * jk/commit-buffer-length: reuse cached commit buffer when parsing signatures commit: record buffer length in cache commit: convert commit->buffer to a slab commit-slab: provide a static initializer use get_commit_buffer everywhere convert logmsg_reencode to get_commit_buffer use get_commit_buffer to avoid duplicate code use get_cached_commit_buffer where appropriate provide helpers to access the commit buffer provide a helper to set the commit buffer provide a helper to free commit buffer sequencer: use logmsg_reencode in get_message logmsg_reencode: return const buffer do not create "struct commit" with xcalloc commit: push commit_index update into alloc_commit_node alloc: include any-object allocations in alloc_report replace dangerous uses of strbuf_attach commit_tree: take a pointer/len pair rather than a const strbuf
2014-07-02Merge branch 'jk/commit-buffer-length'Libravatar Junio C Hamano1-1/+2
Move "commit->buffer" out of the in-core commit object and keep track of their lengths. Use this to optimize the code paths to validate GPG signatures in commit objects. * jk/commit-buffer-length: reuse cached commit buffer when parsing signatures commit: record buffer length in cache commit: convert commit->buffer to a slab commit-slab: provide a static initializer use get_commit_buffer everywhere convert logmsg_reencode to get_commit_buffer use get_commit_buffer to avoid duplicate code use get_cached_commit_buffer where appropriate provide helpers to access the commit buffer provide a helper to set the commit buffer provide a helper to free commit buffer sequencer: use logmsg_reencode in get_message logmsg_reencode: return const buffer do not create "struct commit" with xcalloc commit: push commit_index update into alloc_commit_node alloc: include any-object allocations in alloc_report replace dangerous uses of strbuf_attach commit_tree: take a pointer/len pair rather than a const strbuf
2014-06-30index-pack: use strip_suffix to avoid magic numbersLibravatar Jeff King1-15/+14
We also switch to using strbufs, which lets us avoid the potentially dangerous combination of a manual malloc followed by a strcpy. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-30replace has_extension with ends_withLibravatar Jeff King1-2/+2
These two are almost the same function, with the exception that has_extension only matches if there is content before the suffix. So ends_with(".exe", ".exe") is true, but has_extension would not be. This distinction does not matter to any of the callers, though, and we can just replace uses of has_extension with ends_with. We prefer the "ends_with" name because it is more generic, and there is nothing about the function that requires it to be used for file extensions. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-25Merge branch 'ym/fix-opportunistic-index-update-race' into maintLibravatar Junio C Hamano1-1/+1
"git status", even though it is a read-only operation, tries to update the index with refreshed lstat(2) info to optimize future accesses to the working tree opportunistically, but this could race with a "read-write" operation that modify the index while it is running. Detect such a race and avoid overwriting the index. * ym/fix-opportunistic-index-update-race: read-cache.c: verify index file before we opportunistically update it wrapper.c: add xpread() similar to xread()
2014-06-25Merge branch 'jk/index-pack-report-missing' into maintLibravatar Junio C Hamano1-2/+7
The error reporting from "git index-pack" has been improved to distinguish missing objects from type errors. * jk/index-pack-report-missing: index-pack: distinguish missing objects from type errors
2014-06-25Merge branch 'nd/index-pack-one-fd-per-thread' into maintLibravatar Junio C Hamano1-10/+17
We used to disable threaded "git index-pack" on platforms without thread-safe pread(); use a different workaround for such platforms to allow threaded "git index-pack". * nd/index-pack-one-fd-per-thread: index-pack: work around thread-unsafe pread()
2014-06-13commit: record buffer length in cacheLibravatar Jeff King1-1/+1
Most callsites which use the commit buffer try to use the cached version attached to the commit, rather than re-reading from disk. Unfortunately, that interface provides only a pointer to the NUL-terminated buffer, with no indication of the original length. For the most part, this doesn't matter. People do not put NULs in their commit messages, and the log code is happy to treat it all as a NUL-terminated string. However, some code paths do care. For example, when checking signatures, we want to be very careful that we verify all the bytes to avoid malicious trickery. This patch just adds an optional "size" out-pointer to get_commit_buffer and friends. The existing callers all pass NULL (there did not seem to be any obvious sites where we could avoid an immediate strlen() call, though perhaps with some further refactoring we could). Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-13provide a helper to free commit bufferLibravatar Jeff King1-1/+2
This converts two lines into one at each caller. But more importantly, it abstracts the concept of freeing the buffer, which will make it easier to change later. Note that we also need to provide a "detach" mechanism for a tricky case in index-pack. We are passed a buffer for the object generated by processing the incoming pack. If we are not using --strict, we just calculate the sha1 on that buffer and return, leaving the caller to free it. But if we are using --strict, we actually attach that buffer to an object, pass the object to the fsck functions, and then detach the buffer from the object again (so that the caller can free it as usual). In this case, we don't want to free the buffer ourselves, but just make sure it is no longer associated with the commit. Note that we are making the assumption here that the attach/detach process does not impact the buffer at all (e.g., it is never reallocated or modified). That holds true now, and we have no plans to change that. However, as we abstract the commit_buffer code, this dependency becomes less obvious. So when we detach, let's also make sure that we get back the same buffer that we gave to the commit_buffer code. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-06Merge branch 'jk/index-pack-report-missing'Libravatar Junio C Hamano1-2/+7
* jk/index-pack-report-missing: index-pack: distinguish missing objects from type errors
2014-06-03Merge branch 'nd/index-pack-one-fd-per-thread'Libravatar Junio C Hamano1-10/+17
Enable threaded index-pack on platforms without thread-unsafe pread() emulation. * nd/index-pack-one-fd-per-thread: index-pack: work around thread-unsafe pread()
2014-06-03Merge branch 'ym/fix-opportunistic-index-update-race'Libravatar Junio C Hamano1-1/+1
Read-only operations such as "git status" that internally refreshes the index write out the refreshed index to the disk to optimize future accesses to the working tree, but this could race with a "read-write" operation that modify the index while it is running. Detect such a race and avoid overwriting the index. Duy raised a good point that we may need to do the same for the normal writeout codepath, not just the "opportunistic" update codepath. While that is true, nobody sane would be running two simultaneous operations that are clearly write-oriented competing with each other against the same index file. So in that sense that can be done as a less urgent follow-up for this topic. * ym/fix-opportunistic-index-update-race: read-cache.c: verify index file before we opportunistically update it wrapper.c: add xpread() similar to xread()
2014-05-12index-pack: distinguish missing objects from type errorsLibravatar Jeff King1-2/+7
When we fetch a pack that does not contain an object we expected to receive, we get an error like: $ git init --bare tmp.git && cd tmp.git $ git fetch ../parent.git [...] error: Could not read 964953ec7bcc0245cb1d0db4095455edd21a2f2e fatal: Failed to traverse parents of commit b8247b40caf6704fe52736cdece6d6aae87471aa error: ../parent.git did not send all necessary objects This comes from the check_everything_connected rev-list. If we try cloning the same repo (rather than a fetch), we end up using index-pack's --check-self-contained-and-connected option instead, which produces output like: $ git clone --no-local --bare parent.git tmp.git [...] fatal: object of unexpected type fatal: index-pack failed Not only is the sha1 missing, but it's a misleading message. There's no type problem, but rather a missing object problem; we don't notice the difference because we simply compare OBJ_BAD != OBJ_BLOB. Let's provide a different message for this case: $ git clone --no-local --bare parent.git tmp.git fatal: did not receive expected object 6b00a8c61ed379d5f925a72c1987c9c52129d364 fatal: index-pack failed While we're at it, let's also improve a true type mismatch error to look like fatal: object 6b00a8c61ed379d5f925a72c1987c9c52129d364: expected type blob, got tree Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-04-16index-pack: work around thread-unsafe pread()Libravatar Nguyễn Thái Ngọc Duy1-10/+17
Multi-threaing of index-pack was disabled with c0f8654 (index-pack: Disable threading on cygwin - 2012-06-26), because pread() implementations for Cygwin and MSYS were not thread safe. Recent Cygwin does offer usable pread() and we enabled multi-threading with 103d530f (Cygwin 1.7 has thread-safe pread, 2013-07-19). Work around this problem on platforms with a thread-unsafe pread() emulation by opening one file handle per thread; it would prevent parallel pread() on different file handles from stepping on each other. Also remove NO_THREAD_SAFE_PREAD that was introduced in c0f8654 because it's no longer used anywhere. This workaround is unconditional, even for platforms with thread-safe pread() because the overhead is small (a couple file handles more) and not worth fragmenting the code. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Tested-by: Johannes Sixt <j6t@kdbg.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-04-10wrapper.c: add xpread() similar to xread()Libravatar Yiannis Marangos1-1/+1
It is a common mistake to call read(2)/pread(2) and forget to anticipate that they may return error with EAGAIN/EINTR when the system call is interrupted. We have xread() helper to relieve callers of read(2) from having to worry about it; add xpread() helper to do the same for pread(2). Update the caller in the builtin/index-pack.c and the mmap emulation in compat/. Signed-off-by: Yiannis Marangos <yiannis.marangos@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-04-03Merge branch 'nd/index-pack-error-message' into maintLibravatar Junio C Hamano1-2/+2
* nd/index-pack-error-message: index-pack: report error using the correct variable
2014-03-25Merge branch 'nd/index-pack-error-message'Libravatar Junio C Hamano1-2/+2
* nd/index-pack-error-message: index-pack: report error using the correct variable
2014-03-17index-pack: report error using the correct variableLibravatar Junio C Hamano1-2/+2
We feed a string pointer that is potentially NULL to die() when showing the message. Don't. Noticed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-20rename read_replace_refs to check_replace_refsLibravatar Michael Haggerty1-1/+1
The semantics of this flag was changed in commit e1111cef23 inline lookup_replace_object() calls but wasn't renamed at the time to minimize code churn. Rename it now, and add a comment explaining its use. Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-12-05replace {pre,suf}fixcmp() with {starts,ends}_with()Libravatar Christian Couder1-4/+4
Leaving only the function definitions and declarations so that any new topic in flight can still make use of the old functions, replace existing uses of the prefixcmp() and suffixcmp() with new API functions. The change can be recreated by mechanically applying this: $ git grep -l -e prefixcmp -e suffixcmp -- \*.c | grep -v strbuf\\.c | xargs perl -pi -e ' s|!prefixcmp\(|starts_with\(|g; s|prefixcmp\(|!starts_with\(|g; s|!suffixcmp\(|ends_with\(|g; s|suffixcmp\(|!ends_with\(|g; ' on the result of preparatory changes in this series. Signed-off-by: Christian Couder <chriscool@tuxfamily.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-09-17Merge branch 'jk/free-tree-buffer'Libravatar Junio C Hamano1-0/+1
* jk/free-tree-buffer: clear parsed flag when we free tree buffers
2013-06-06clear parsed flag when we free tree buffersLibravatar Jeff King1-0/+1
Many code paths will free a tree object's buffer and set it to NULL after finishing with it in order to keep memory usage down during a traversal. However, out of 8 sites that do this, only one actually unsets the "parsed" flag back. Those sites that don't are setting a trap for later users of the tree object; even after calling parse_tree, the buffer will remain NULL, causing potential segfaults. It is not known whether this is triggerable in the current code. Most commands do not do an in-memory traversal followed by actually using the objects again. However, it does not hurt to be safe for future callers. In most cases, we can abstract this out to a "free_tree_buffer" helper. However, there are two exceptions: 1. The fsck code relies on the parsed flag to know that we were able to parse the object at one point. We can switch this to using a flag in the "flags" field. 2. The index-pack code sets the buffer to NULL but does not free it (it is freed by a caller). We should still unset the parsed flag here, but we cannot use our helper, as we do not want to free the buffer. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-28clone: open a shortcut for connectivity checkLibravatar Nguyễn Thái Ngọc Duy1-9/+26
In order to make sure the cloned repository is good, we run "rev-list --objects --not --all $new_refs" on the repository. This is expensive on large repositories. This patch attempts to mitigate the impact in this special case. In the "good" clone case, we only have one pack. If all of the following are met, we can be sure that all objects reachable from the new refs exist, which is the intention of running "rev-list ...": - all refs point to an object in the pack - there are no dangling pointers in any object in the pack - no objects in the pack point to objects outside the pack The second and third checks can be done with the help of index-pack as a slight variation of --strict check (which introduces a new condition for the shortcut: pack transfer must be used and the number of objects large enough to call index-pack). The first is checked in check_everything_connected after we get an "ok" from index-pack. "index-pack + new checks" is still faster than the current "index-pack + rev-list", which is the whole point of this patch. If any of the conditions fail, we fall back to the good old but expensive "rev-list ..". In that case it's even more expensive because we have to pay for the new checks in index-pack. But that should only happen when the other side is either buggy or malicious. Cloning linux-2.6 over file:// before after real 3m25.693s 2m53.050s user 5m2.037s 4m42.396s sys 0m13.750s 0m16.574s A more realistic test with ssh:// over wireless before after real 11m26.629s 10m4.213s user 5m43.196s 5m19.444s sys 0m35.812s 0m37.630s This shortcut is not applied to shallow clones, partly because shallow clones should have no more objects than a usual fetch and the cost of rev-list is acceptable, partly to avoid dealing with corner cases when grafting is involved. This shortcut does not apply to unpack-objects code path either because the number of objects must be small in order to trigger that code path. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-05-28index-pack: remove dead code (it should never happen)Libravatar Nguyễn Thái Ngọc Duy1-2/+1
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-04-01Merge branch 'nd/index-pack-threaded-fixes'Libravatar Junio C Hamano1-8/+26
"index-pack --verify-stat" used a few counters outside protection of mutex, possibly showing incorrect numbers. * nd/index-pack-threaded-fixes: index-pack: guard nr_resolved_deltas reads by lock index-pack: protect deepest_delta in multithread code
2013-04-01Merge branch 'jk/index-pack-correct-depth-fix'Libravatar Junio C Hamano1-0/+2
"index-pack --fix-thin" used uninitialize value to compute delta depths of objects it appends to the resulting pack. * jk/index-pack-correct-depth-fix: index-pack: always zero-initialize object_entry list
2013-03-20index-pack: always zero-initialize object_entry listLibravatar Jeff King1-0/+2
Commit 38a4556 (index-pack: start learning to emulate "verify-pack -v", 2011-06-03) added a "delta_depth" counter to each "struct object_entry". Initially, all object entries have their depth set to 0; in resolve_delta, we then set the depth of each delta to "base + 1". Base entries never have their depth touched, and remain at 0. To ensure that all depths start at 0, that commit changed calls to xmalloc the object_entry list into calls to xcalloc. However, it forgot that we grow the list with xrealloc later. These extra entries are used when we add an object from elsewhere to complete a thin pack. If we add a non-delta object, its depth value will just be uninitialized heap data. This patch fixes it by zero-initializing entries we add to the objects list via the xrealloc. Signed-off-by: Jeff King <peff@peff.net> Acked-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-03-19index-pack: guard nr_resolved_deltas reads by lockLibravatar Thomas Rast1-1/+3
The threaded parts of index-pack increment the number of resolved deltas in nr_resolved_deltas guarded by counter_mutex. However, the per-thread outer loop accessed nr_resolved_deltas without any locks. This is not wrong as such, since it doesn't matter all that much whether we get an outdated value. However, unless someone proves that this one lock makes all the performance difference, it would be much cleaner to guard _all_ accesses to the variable with the lock. The only such use is display_progress() in the threaded section (all others are in the conclude_pack() callchain outside the threaded part). To make it obvious that it cannot deadlock, move it out of work_mutex. Signed-off-by: Thomas Rast <trast@student.ethz.ch> Reviewed-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-03-19index-pack: protect deepest_delta in multithread codeLibravatar Nguyễn Thái Ngọc Duy1-7/+23
deepest_delta is a global variable but is updated without protection in resolve_delta(), a multithreaded function. Add a new mutex for it, but only protect and update when it's actually used (i.e. show_stat is non-zero). Another variable that will not be updated is delta_depth in "struct object_entry" as it's only useful when show_stat is 1. Putting it in "if (show_stat)" makes it clearer. The local variable "stat" is renamed to "show_stat" after moving to global scope because the name "stat" conflicts with stat(2) syscall. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Reviewed-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-03-16index-pack: fix buffer overflow caused by translationsLibravatar Nguyễn Thái Ngọc Duy1-4/+5
The translation of "completed with %d local objects" is put in a 48-byte buffer, which may be enough for English but not true for any translations. Convert it to use strbuf (i.e. no hard limit on translation length). Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-08-31i18n: mark more index-pack strings for translationLibravatar Nguyễn Thái Ngọc Duy1-10/+11
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-07-15Merge branch 'jk/index-pack-streaming-fix'Libravatar Junio C Hamano1-10/+13
The streaming index-pack introduced in 1.7.11 had a data corruption bug, and this should fix it. * jk/index-pack-streaming-fix: index-pack: loop while inflating objects in unpack_data
2012-07-10index-pack: loop while inflating objects in unpack_dataLibravatar Jeff King1-10/+13
When the unpack_data function is given a consume() callback, it unpacks only 64K of the input at a time, feeding it to git_inflate along with a 64K output buffer. However, because we are inflating, there is a good chance that the output buffer will fill before consuming all of the input. In this case, we need to loop on git_inflate until we have fed the whole input buffer, feeding each chunk of output to the consume buffer. The current code does not do this, and as a result, will fail the loop condition and trigger a fatal "serious inflate inconsistency" error in this case. While we're rearranging the loop, let's get rid of the extra last_out pointer. It is meant to point to the beginning of the buffer that we feed to git_inflate, but in practice this is always the beginning of our same 64K buffer, because: 1. At the beginning of the loop, we are feeding the buffer. 2. At the end of the loop, if we are using a consume() function, we reset git_inflate's pointer to the beginning of the buffer. If we are not using a consume() function, then we do not care about the value of last_out at all. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-07-09Merge branch 'rj/platform-pread-may-be-thread-unsafe'Libravatar Junio C Hamano1-2/+2
On Cygwin, the platform pread(3) is not thread safe, just like our own compat/ emulation, and cannot be used in the index-pack program. * rj/platform-pread-may-be-thread-unsafe: index-pack: Disable threading on cygwin
2012-06-26index-pack: Disable threading on cygwinLibravatar Junio C Hamano1-2/+2
The Cygwin implementation of pread() is not thread-safe since, just like the emulation provided by compat/pread.c, it uses a sequence of seek-read-seek calls. In order to avoid failues due to thread-safety issues, commit b038a61 disables threading when NO_PREAD is defined. (ie when using the emulation code in compat/pread.c). We introduce a new build variable, NO_THREAD_SAFE_PREAD, which allows use to disable the threaded index-pack code on cygwin, in addition to the above NO_PREAD case. Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-24index-pack: use streaming interface for collision test on large blobsLibravatar Nguyễn Thái Ngọc Duy1-5/+77
When putting whole objects in core is unavoidable, try match object type and size first before actually inflating. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-23index-pack: factor out unpack core from get_data_from_packLibravatar Nguyễn Thái Ngọc Duy1-3/+24
This allows caller to consume large inflated object with a fixed amount of memory. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-23index-pack: use streaming interface on large blobs (most of the time)Libravatar Nguyễn Thái Ngọc Duy1-8/+44
unpack_raw_entry() will not allocate and return decompressed blobs if they are larger than core.bigFileThreshold. sha1_object() may not be called on those objects because there's no actual content. sha1_object() is called later on those objects, where we can safely use get_data_from_pack() to retrieve blob content for checking. However we always do that when we definitely need the blob content. And we often don't. There are two cases when we may need object content. The first case is when we find an in-repo blob with the same SHA-1. We need to do collision test, byte-on-byte. If this test is on, the blob must be loaded on memory (i.e. no streaming). Normally (e.g. in fetch/pull/clone) this does not happen because git avoid to send objects that client already has. The other case is when --strict is specified and the object in question is not a blob, which can't happen in reality becase we deal with large _blobs_ here. Note: --verify (or git-verify-pack) a pack from current repository will trigger collision test on every object in the pack, which effectively disables this patch. This could be easily worked around by setting GIT_DIR to an imaginary place with no packs. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-23index-pack: hash non-delta objects while reading from streamLibravatar Nguyễn Thái Ngọc Duy1-11/+30
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-14Merge branch 'nd/threaded-index-pack'Libravatar Junio C Hamano1-66/+275
Enables threading in index-pack to resolve base data in parallel. By Nguyễn Thái Ngọc Duy (3) and Ramsay Jones (1) * nd/threaded-index-pack: index-pack: disable threading if NO_PREAD is defined index-pack: support multithreaded delta resolving index-pack: restructure pack processing into three main functions compat/win32/pthread.h: Add an pthread_key_delete() implementation
2012-05-07index-pack: disable threading if NO_PREAD is definedLibravatar Nguyễn Thái Ngọc Duy1-0/+5
NO_PREAD simulates pread() as a sequence of seek, read, seek in compat/pread.c. The simulation is not thread-safe because another thread could move the file offset away in the middle of pread operation. Do not allow threading in that case. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-07index-pack: support multithreaded delta resolvingLibravatar Nguyễn Thái Ngọc Duy1-11/+193
This puts delta resolving on each base on a separate thread, one base cache per thread. Per-thread data is grouped in struct thread_local. When running with nr_threads == 1, no pthreads calls are made. The system essentially runs in non-thread mode. An experiment on a Xeon 24 core machine with git.git shows that performance does not increase proportional to the number of cores. So by default, we use maximum 3 cores. Some numbers with --threads from 1 to 16: 1..4 real 0m8.003s 0m5.307s 0m4.321s 0m3.830s user 0m7.720s 0m8.009s 0m8.133s 0m8.305s sys 0m0.224s 0m0.372s 0m0.360s 0m0.360s 5..8 real 0m3.727s 0m3.604s 0m3.332s 0m3.369s user 0m9.361s 0m9.817s 0m9.525s 0m9.769s sys 0m0.584s 0m0.624s 0m0.540s 0m0.560s 9..12 real 0m3.036s 0m3.139s 0m3.177s 0m2.961s user 0m8.977s 0m10.205s 0m9.737s 0m10.073s sys 0m0.596s 0m0.680s 0m0.684s 0m0.680s 13..16 real 0m2.985s 0m2.894s 0m2.975s 0m2.971s user 0m9.825s 0m10.573s 0m10.833s 0m11.361s sys 0m0.788s 0m0.732s 0m0.904s 0m1.016s On an Intel dual core and linux-2.6.git 1..4 real 2m37.789s 2m7.963s 2m0.920s 1m58.213s user 2m28.415s 2m52.325s 2m50.176s 2m41.187s sys 0m7.808s 0m11.181s 0m11.224s 0m10.731s Thanks Ramsay Jones for troubleshooting and support on MinGW platform. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-05-07index-pack: restructure pack processing into three main functionsLibravatar Nguyễn Thái Ngọc Duy1-53/+75
The second pass in parse_pack_objects() are split into resolve_deltas(). The final phase, fixing thin pack or just seal the pack, is now in conclude_pack() function. Main pack processing is now a sequence of these functions: - parse_pack_objects() reads through the input pack - resolve_deltas() makes sure all deltas can be resolved - conclude_pack() seals the output pack - write_idx_file() writes companion index file - final() moves the pack/index to proper place Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-04-24i18n: index-pack: mark strings for translationLibravatar Nguyễn Thái Ngọc Duy1-57/+68
Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-01-16index-pack: eliminate unlimited recursion in get_base_data()Libravatar Nguyễn Thái Ngọc Duy1-9/+44
Revese the order of delta applying so that by the time a delta is applied, its base is either non-delta or already inflated. get_base_data() is still recursive, but because base's data is always ready, the inner get_base_data() call never has any chance to call itself again. Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>