54 lines
2.3 KiB
Plaintext
54 lines
2.3 KiB
Plaintext
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This is a list of projects for CVS. In general, unlike the things in
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the TODO file, these need more analysis to determine if and how
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worthwhile each task is.
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I haven't gone through TODO, but it's likely that it has entries that
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are actually more appropriate for this list.
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0. Improved Efficency
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* CVS uses a single doubly linked list/hash table data structure for
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all of its lists. Since the back links are only used for deleting
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list nodes it might be beneficial to use singly linked lists or a
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tree structure. Most likely, a single list implementation will not
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be appropriate for all uses.
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One easy change would be to remove the "type" field out of the list
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and node structures. I have found it to be of very little use when
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debugging, and each instance eats up a word of memory. This can add
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up and be a problem on memory-starved machines.
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Profiles have shown that on fast machines like the Alpha, fsortcmp()
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is one of the hot spots.
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* Dynamically allocated character strings are created, copied, and
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destroyed throughout CVS. The overhead of malloc()/strcpy()/free()
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needs to be measured. If significant, it could be minimized by using a
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reference counted string "class".
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* File modification time is stored as a character string. It might be
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worthwile to use a time_t internally if the time to convert a time_t
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(from struct stat) to a string is greater that the time to convert a
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ctime style string (from the entries file) to a time_t. time_t is
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an machine-dependant type (although it's pretty standard on UN*X
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systems), so we would have to have different conversion routines.
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Profiles show that both operations are called about the same number
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of times.
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* stat() is one of the largest performance bottlenecks on systems
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without the 4.4BSD filesystem. By spliting information out of
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the filesystem (perhaps the "rename database") we should be
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able to improve performance.
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* Parsing RCS files is very expensive. This might be unnecessary if
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RCS files are only used as containers for revisions, and tag,
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revision, and date information was available in easy to read
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(and modify) indexes. This becomes very apparent with files
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with several hundred revisions.
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1. Improved testsuite/sanity check script
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* Need to use a code coverage tool to determine how much the sanity
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script tests, and fill in the holes.
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