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* Revert "pack-objects: only throw away data during memory pressure"Junio C Hamano2008-02-121-11/+2
| | | | | | | | | | | | | | | | | | | | This reverts commit 9c2174350cc0ae0f6bad126e15fe1f9f044117ab. Nico analyzed and found out that this does not really help, and I agree with it. By the time this gets into action and data is actively thrown away, performance simply goes down the drain due to the data constantly being reloaded over and over and over and over and over and over again, to the point of virtually making no relative progress at all. The previous behavior of enforcing the memory limit by dynamically shrinking the window size at least had the effect of allowing some kind of progress, even if the end result wouldn't be optimal. And that's the whole point behind this memory limiting feature: allowing some progress to be made when resources are too limited to let the repack go unbounded.
* pack-objects: only throw away data during memory pressureMartin Koegler2008-02-111-2/+11
| | | | | | | | | | | If pack-objects hit the memory limit, it deletes objects from the delta window. This patch make it only delete the data, which is recomputed, if needed again. Signed-off-by: Martin Koegler <mkoegler@auto.tuwien.ac.at> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: Fix segfault when object count is less than thread countNicolas Pitre2008-01-211-1/+2
| | | | | | | | | | | When partitioning the work amongst threads, dividing the number of objects by the number of threads may return 0 when there are less objects than threads; this will cause the subsequent code to segfault when accessing list[sub_size-1]. Allow some threads to have zero objects to work on instead of barfing, while letting others to have more. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: remove redundant and wrong call to deflateEnd()Junio C Hamano2008-01-101-1/+1
| | | | | | | | | | | | | | | | We somehow called deflateEnd() on a stream that we have called deflateEnd() on already. In fact, the second deflateEnd() has always been returning Z_STREAM_ERROR. We just never checked the error return from that particular deflateEnd(). The first one returns 0 for success. We might want to tighten the check even more to check that. Noticed by Marco. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Don't access line[-1] for a zero-length "line" from fgets.Jim Meyering2008-01-041-1/+1
| | | | | | | | | | | | | | | A NUL byte at beginning of file, or just after a newline would provoke an invalid buf[-1] access in a few places. * builtin-grep.c (cmd_grep): Don't access buf[-1]. * builtin-pack-objects.c (get_object_list): Likewise. * builtin-rev-list.c (read_revisions_from_stdin): Likewise. * bundle.c (read_bundle_header): Likewise. * server-info.c (read_pack_info_file): Likewise. * transport.c (insert_packed_refs): Likewise. Signed-off-by: Jim Meyering <meyering@redhat.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Plug a resource leak in threaded pack-objects code.Johannes Sixt2007-12-171-2/+2
| | | | | | | | | | | A mutex and a condition variable is allocated for each thread and torn down when the thread terminates. However, for certain workloads it can happen that some threads are actually not started at all. In this case we would leak the mutex and condition variable. Now we allocate them only for those threads that are actually started. Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* threaded pack-objects: Use condition variables for thread communication.Johannes Sixt2007-12-161-50/+79
| | | | | | | | | | | | | | | | | | | | In the threaded pack-objects code the main thread and the worker threads must mutually signal that they have assigned a new pack of work or have completed their work, respectively. Previously, the code used mutexes that were locked in one thread and unlocked from a different thread, which is bogus (and happens to work on Linux). Here we rectify the implementation by using condition variables: There is one condition variable on which the main thread waits until a thread requests new work; and each worker thread has its own condition variable on which it waits until it is assigned new work or signaled to terminate. As a cleanup, the worker threads are spawned only after the initial work packages have been assigned. Signed-off-by: Johannes Sixt <johannes.sixt@telecom.at> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: more threaded load balancing fix with often changed pathsNicolas Pitre2007-12-101-0/+10
| | | | | | | | | | | The code that splits the object list amongst work threads tries to do so on "path" boundaries not to prevent good delta matches. However, in some cases, a few paths may largely dominate the hash distribution and it is not possible to have good load balancing without ignoring those boundaries. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: fix threaded load balancingNicolas Pitre2007-12-081-32/+85
| | | | | | | | | | | | | | | | | | | | The current method consists of a master thread serving chunks of objects to work threads when they're done with their previous chunk. The issue is to determine the best chunk size: making it too large creates poor load balancing, while making it too small has a negative effect on pack size because of the increased number of chunk boundaries and poor delta window utilization. This patch implements a completely different approach by initially splitting the work in large chunks uniformly amongst all threads, and whenever a thread is done then it steals half of the remaining work from another thread with the largest amount of unprocessed objects. This has the advantage of greatly reducing the number of chunk boundaries with an almost perfect load balancing. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: reverse the delta search sort listNicolas Pitre2007-12-081-20/+21
| | | | | | | | | | | | | | | It is currently sorted and then walked backward. Not only this doesn't feel natural for my poor brain, but it would make the next patch less obvious as well. So reverse the sort order, and reverse the list walking direction, which effectively produce the exact same end result as before. Also bring the relevant comment nearer the actual code and adjust it accordingly, with minor additional clarifications. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: fix delta cache size accountingNicolas Pitre2007-12-081-5/+5
| | | | | | | | | | | The wrong value was substracted from delta_cache_size when replacing a cached delta, as trg_entry->delta_size was used after the old size had been replaced by the new size. Noticed by Linus. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Fix rev-list when showing objects involving submodulesLinus Torvalds2007-11-141-1/+1
| | | | | | | | | | | | | | | | | | The function mark_tree_uninteresting() assumed that the tree entries are blob when they are not trees. This is not so. Since we do not traverse into submodules (yet), the gitlinks should be ignored. In general, we should try to start moving away from using the "S_ISLNK()" like things for internal git state. It was a mistake to just assume the numbers all were same across all systems in the first place. This implementation converts to the "object_type", and then uses a case statement. Noticed by Ilari on IRC. Test script taken from an earlier version by Dscho. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Merge branch 'np/pack'Junio C Hamano2007-11-041-7/+12
|\ | | | | | | | | | | | | | | | | | | * np/pack: pack-objects: get rid of an ugly cast make the pack index version configurable Conflicts: builtin-pack-objects.c
| * pack-objects: get rid of an ugly castNicolas Pitre2007-11-021-6/+6
| | | | | | | | | | | | | | ... when calling write_idx_file(). Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
| * make the pack index version configurableNicolas Pitre2007-11-021-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | It is a good idea to use pack index version 2 all the time since it has proper protection against propagation of certain pack corruptions when repacking which is not possible with index version 1, as demonstrated in test t5302. Hence this config option. The default is still pack index version 1. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | add throughput display to git-pushNicolas Pitre2007-10-301-1/+1
| | | | | | | | | | | | | | | | | | This one triggers only when git-pack-objects is called with --all-progress and --stdout which is the combination used by git-push. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | relax usage of the progress APINicolas Pitre2007-10-301-12/+6
| | | | | | | | | | | | | | | | | | | | Since it is now OK to pass a null pointer to display_progress() and stop_progress() resulting in a no-op, then we can simplify the code and remove a bunch of lines by not making those calls conditional all the time. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | make struct progress an opaque typeNicolas Pitre2007-10-301-8/+8
| | | | | | | | | | | | | | | | | | This allows for better management of progress "object" existence, as well as making the progress display implementation more independent from its callers. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | Change 'Deltifying objects' to 'Compressing objects'Shawn O. Pearce2007-10-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | Recently I was referred to the Grammar Police as the git-pack-objects progress message 'Deltifying %u objects' is considered to be not proper English to at least some small but vocal segment of the English speaking population. Techncially we are applying delta compression to these objects at this stage, so the new term is slightly more acceptable to the Grammar Police but is also just as correct. Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* | fix const issues with some functionsNicolas Pitre2007-10-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Two functions, namely write_idx_file() and open_pack_file(), currently return a const pointer. However that pointer is either a copy of the first argument, or set to a malloc'd buffer when that first argument is null. In the later case it is wrong to qualify that pointer as const since ownership of the buffer is transferred to the caller to dispose of, and obviously the free() function is not meant to be passed const pointers. Making the return pointer not const causes a warning when the first argument is returned since that argument is also marked const. The correct thing to do is therefore to remove the const qualifiers, avoiding the need for ugly casts only to silence some warnings. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* | pack-objects.c: fix some global variable abuse and memory leaksNicolas Pitre2007-10-171-14/+15
| | | | | | | | | | | | | | | | | | | | | | To keep things well layered, sha1close() now returns the file descriptor when it doesn't close the file. An ugly cast was added to the return of write_idx_file() to avoid a warning. A proper fix will come separately. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* | pack-objects: no delta possible with only one object in the listNicolas Pitre2007-10-171-1/+1
| | | | | | | | | | | | | | | | ... so don't even try in that case, and save another useless line of progress display. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* | more compact progress displayNicolas Pitre2007-10-171-11/+5
|/ | | | | | | | | | | Each progress can be on a single line instead of two. [sp: Changed "Checking files out" to "Checking out files" at Johannes Sixt's suggestion as it better explains the action that is taking place] Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
* Merge branch 'jc/autogc'Junio C Hamano2007-10-031-2/+93
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | * jc/autogc: git-gc --auto: run "repack -A -d -l" as necessary. git-gc --auto: restructure the way "repack" command line is built. git-gc --auto: protect ourselves from accumulated cruft git-gc --auto: add documentation. git-gc --auto: move threshold check to need_to_gc() function. repack -A -d: use --keep-unreachable when repacking pack-objects --keep-unreachable Export matches_pack_name() and fix its return value Invoke "git gc --auto" from commit, merge, am and rebase. Implement git gc --auto
| * pack-objects --keep-unreachableJunio C Hamano2007-09-171-2/+93
| | | | | | | | | | | | | | | | | | | | | | This new option is meant to be used in conjunction with the options "git repack -a -d" usually invokes the underlying pack-objects with. When this option is given, objects unreachable from the refs in packs named with --unpacked= option are added to the resulting pack, in addition to the reachable objects that are not in packs marked with *.keep files. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | builtin-pack-objects.c: avoid bogus gcc warningsJunio C Hamano2007-09-141-6/+6
| | | | | | | | | | | | | | These empty statement marcos can solicit bogus "statement with no effect" warnings; squelch them. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | threaded delta search: proper locking for cache accountingNicolas Pitre2007-09-121-4/+20
| | | | | | | | | | Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | threaded delta search: add pack.threads config variableNicolas Pitre2007-09-101-0/+11
| | | | | | | | | | Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | fix threaded delta search lockingNicolas Pitre2007-09-101-5/+6
| | | | | | | | | | | | | | Found by Jeff King. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | threaded delta search: specify number of threads at run timeNicolas Pitre2007-09-091-5/+21
| | | | | | | | | | | | | | | | This adds a --threads=<n> parameter to 'git pack-objects' with documentation. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | threaded delta search: better chunck split pointNicolas Pitre2007-09-091-0/+5
| | | | | | | | | | | | | | | | | | Try to keep object with the same name hash together. Suggested by Martin Koegler. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | threaded delta search: refine work allocationNicolas Pitre2007-09-091-14/+45
| | | | | | | | | | | | | | | | | | | | With this, each thread get repeatedly assigned the next available chunk of objects to process until the whole list is done. The idea is to have reasonably small chunks so that all CPUs remain busy with a minimum number of threads for as long as there is data to process. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | basic threaded delta searchNicolas Pitre2007-09-061-1/+82
| | | | | | | | | | | | | | | | | | | | | | | | | | | | this is still rough, hence it is disabled by default. You need to compile with "make THREADED_DELTA_SEARCH=1 ..." at the moment. Threading is done on different portions of the object list to be deltified. This is currently done by spliting the list into n parts and then a thread is spawned for each of them. A better method would consist of spliting the list into more smaller parts and have the n threads pick the next part available. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | rearrange delta search progress reportingNicolas Pitre2007-09-061-9/+14
| | | | | | | | | | | | | | | | This is to help threadification of the delta search code, with a bonus consistency check. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | localize window memory usage accountingNicolas Pitre2007-09-051-14/+14
| | | | | | | | | | | | | | This is to help threadification of delta searching. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | straighten the list of objects to deltifyNicolas Pitre2007-09-051-35/+42
| | | | | | | | | | | | | | | | Not all objects are subject to deltification, so avoid carrying those along, and provide the real count to progress display. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* | Keep last used delta base in the delta windowJunio C Hamano2007-09-011-2/+23
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is based on Martin Koegler's idea to keep the object that was successfully used as the base of the delta when it is about to fall off the edge of the window. Instead of doing so only for the objects at the edge of the window, this makes the window a lru eviction mechanism. If an entry is used as a base, it is moved to the last of the queue to be evicted. This is a quick-and-dirty implementation, as it keeps the original implementation of the data structure used for the window. This originally was done as an array, not as an array of pointers, because it was meant to be used as a cyclic FIFO buffer and a plain array avoids an extra pointer indirection, while its FIFOness eant that we are not "moving" the entries like this patch does. The runtime from three versions were comparable. It seems to make the resulting chain even shorter, which can only be good. (stock "master") 15782196 bytes chain length = 1: 2972 objects chain length = 2: 2651 objects chain length = 3: 2369 objects chain length = 4: 2121 objects chain length = 5: 1877 objects ... chain length = 46: 490 objects chain length = 47: 515 objects chain length = 48: 527 objects chain length = 49: 570 objects chain length = 50: 408 objects (with your patch) 15745736 bytes (0.23% smaller) chain length = 1: 3137 objects chain length = 2: 2688 objects chain length = 3: 2322 objects chain length = 4: 2146 objects chain length = 5: 1824 objects ... chain length = 46: 503 objects chain length = 47: 509 objects chain length = 48: 536 objects chain length = 49: 588 objects chain length = 50: 357 objects (with this patch) 15612086 bytes (1.08% smaller) chain length = 1: 4831 objects chain length = 2: 3811 objects chain length = 3: 2964 objects chain length = 4: 2352 objects chain length = 5: 1944 objects ... chain length = 46: 327 objects chain length = 47: 353 objects chain length = 48: 304 objects chain length = 49: 298 objects chain length = 50: 135 objects [jc: this is with code simplification follow-up from Nico] Signed-off-by: Junio C Hamano <gitster@pobox.com>
* fix same sized delta logicNicolas Pitre2007-08-301-4/+8
| | | | | | | | | The code favoring shallower deltas when size is equal was triggered only when previous delta was also cached. There should be no relation between cached deltas and same sized deltas. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: check return value from read_sha1_file()Junio C Hamano2007-08-251-0/+6
| | | | Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Make thin-pack generation subproject aware.Linus Torvalds2007-08-191-0/+2
| | | | | | | | | | | | When a thin pack wants to send a tree object at "sub/dir", and the commit that is common between the sender and the receiver that is used as the base object has a subproject at that path, we should not try to use the data at "sub/dir" of the base tree as a tree object. It is not a tree to begin with, and more importantly, the commit object there does not have to even exist. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: remove bogus arguments to delta_cacheable()Nicolas Pitre2007-08-151-4/+3
| | | | | | | | Not only are they unused, but the order in the function declaration and the actual usage don't match. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Use xmkstemp() instead of mkstemp()Luiz Fernando N. Capitulino2007-08-141-3/+1
| | | | | | | | xmkstemp() performs error checking and prints a standard error message when an error occur. Signed-off-by: Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Pack-objects: properly initialize the depth valueNicolas Pitre2007-07-121-0/+1
| | | | | | | | | | Commit 5a235b5e was missing this little detail. Otherwise your pack will explode. Problem noted by Brian Downing. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* reduce git-pack-objects memory usage a little moreNicolas Pitre2007-07-121-10/+9
| | | | | | | | The delta depth doesn't have to be stored in the global object array structure since it is only used during the deltification pass. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Add pack-objects window memory usage limitBrian Downing2007-07-121-8/+44
| | | | | | | | | | | | | | | | | | | | | | This adds an option (--window-memory=N) and configuration variable (pack.windowMemory = N) to limit the memory size of the pack-objects delta search window. This works by removing the oldest unpacked objects whenever the total size goes above the limit. It will always leave at least one object, though, so as not to completely eliminate the possibility of computing deltas. This is an extra limit on top of the normal window size (--window=N); the window will not dynamically grow above the fixed number of entries specified to fill the memory limit. With this, repacking a repository with a mix of large and small objects is possible even with a very large window. Cleaner and correct circular buffer handling courtesy of Nicolas Pitre. Signed-off-by: Brian Downing <bdowning@lavos.net> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Don't try to delta if target is much smaller than sourceBrian Downing2007-07-121-0/+2
| | | | | | | | | | | | | | | Add a new try_delta heuristic. Don't bother trying to make a delta if the target object size is much smaller (currently 1/32) than the source, as it's very likely not going to get a match. Even if it does, you will have to read at least 32x the size of the new file to reassemble it, which isn't such a good deal. This leads to a considerable performance improvement when deltifying a mix of small and large files with a very large window, because you don't have to wait for the large files to percolate out of the window before things start going fast again. Signed-off-by: Brian Downing <bdowning@lavos.net> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* apply delta depth bias to already deltified objectsNicolas Pitre2007-07-121-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | We already apply a bias on the initial delta attempt with max_size being a function of the base object depth. This has the effect of favoring shallower deltas even if deeper deltas could be smaller, and therefore creating a wider delta tree (see commits 4e8da195 and c3b06a69). This principle should also be applied to all delta attempts for the same object and not only the first attempt. With this the criteria for the best delta is not only its size but also its depth, so that a shallower delta might be selected even if it is larger than a deeper one. Even if some deltas get larger, they allow for wider delta trees making the depth limit less quickly reached and therefore better deltas can be subsequently found, keeping the resulting pack size even smaller. Runtime access to the pack should also benefit from shallower deltas. Testing on different repositories showed slighter faster repacks, smaller resulting packs, and a much nicer curve for delta depth distribution with no more peak at the maximum depth level. Improvements are even more significant with smaller depth limits. Signed-off-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* pack-objects: Prefer shallower deltas if the size is equalBrian Downing2007-07-081-1/+7
| | | | | | | | | Change "try_delta" so that if it finds a delta that has the same size but shallower depth than the existing delta, it will prefer the shallower one. This makes certain delta trees vastly less deep. Signed-off-by: Brian Downing <bdowning@lavos.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
* War on whitespaceJunio C Hamano2007-06-071-1/+1
| | | | | | | | | This uses "git-apply --whitespace=strip" to fix whitespace errors that have crept in to our source files over time. There are a few files that need to have trailing whitespaces (most notably, test vectors). The results still passes the test, and build result in Documentation/ area is unchanged. Signed-off-by: Junio C Hamano <gitster@pobox.com>
* Unify write_index_file functionsGeert Bosch2007-06-021-170/+52
| | | | | | | | | | | | This patch unifies the write_index_file functions in builtin-pack-objects.c and index-pack.c. As the name "index" is overloaded in git, move in the direction of using "idx" and "pack idx" when refering to the pack index. There should be no change in functionality. Signed-off-by: Geert Bosch <bosch@gnat.com> Acked-by: Nicolas Pitre <nico@cam.org> Signed-off-by: Junio C Hamano <junkio@cox.net>