store: don't read the whole fncache in memory In large repositories with lot of files, the fncache grows more than 100 MB and reading that whole thing into memory slows things down. Let's not read the whole thing into memory. This patch changes fncache loading code to read 1 MB at once. Loading 1 MB at once saves ~1 sec on perffncacheload for our internal repository. I tried various values such as 0.5 MB, 5 MB, 10 MB but best results were produced using 1 MB as the chunksize. On a narrow clone with fncache around 40 MB, this patch saves ~0.04 seconds on average on perffncacheload. To test the code, I have coded an extension in test-fncache.t which set chunksize to 1 byte, and the test passes with that. Differential Revision: https://phab.mercurial-scm.org/D5296

wix: restore COPYING.rtf 8427fea04017 accidentally blew away the content of this file. As part of restoring the content, I updated the copyright year to 2019. Differential Revision: https://phab.mercurial-scm.org/D6098

store: move logic to check for invalid entry in fncache to own function This helps separate the original reading logic from the one which finds for an invalid entry. Differential Revision: https://phab.mercurial-scm.org/D6030

py3: add test-phabricator.py to python3-whitelist Differential Revision: https://phab.mercurial-scm.org/D6114

py3: convert to/from bytes/unicode for json.(dump|load)s in debugcallconduit Differential Revision: https://phab.mercurial-scm.org/D6113

py3: use pycompat.byteskwargs on opts in phabricator.py Differential Revision: https://phab.mercurial-scm.org/D6107