@matheusbsbs / matheus-bagliano / commits / 429160544d

ieot: default to not writing IEOT section

As with EOIE, popular versions of Git do not support the new IEOT extension yet. When accessing a Git repository written by a more modern version of Git, they correctly ignore the unrecognized section, but in the process they loudly warn ignoring IEOT extension resulting in confusion for users. Introduce the index extension more gently by not writing it yet in this first version with support for it. Soon, once sufficiently many users are running a modern version of Git, we can flip the default so users benefit from this index extension by default. Introduce a '[index] recordOffsetTable' configuration variable to control whether the new index extension is written. Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>

Jonathan Nieder committed Nov 19, 2018 at 22:12 UTC 429160544db9cc0cf748cdc98b21bd3533ec85a3

2 files changed +17 -1

Documentation/config/index.txt

@@ -5,6 +5,13 @@ index.recordEndOfIndexEntries::

5 reading the index using Git versions before 2.20. Defaults to

6 'false'.

8 +index.recordOffsetTable::

9 + Specifies whether the index file should include an "Index Entry

10 + Offset Table" section. This reduces index load time on

11 + multiprocessor machines but produces a message "ignoring IEOT

12 + extension" when reading the index using Git versions before 2.20.

13 + Defaults to 'false'.

14 +

15 index.threads::

16 Specifies the number of threads to spawn when loading the index.

17 This is meant to reduce index load time on multiprocessor machines.

read-cache.c

+10 -1

@@ -2698,6 +2698,15 @@ static int record_eoie(void)

2698 return 0;

2699 }

2700

2701 +static int record_ieot(void)

2702 +{

2703 + int val;

2704 +

2705 + if (!git_config_get_bool("index.recordoffsettable", &val))

2706 + return val;

2707 + return 0;

2708 +}

2709 +

2710 /*

2711 * On success, `tempfile` is closed. If it is the temporary file

2712 * of a `struct lock_file`, we will therefore effectively perform

@@ -2761,7 +2770,7 @@ static int do_write_index(struct index_state *istate, struct tempfile *tempfile,

2770 else

2771 nr_threads = 1;

2772

2764 - if (nr_threads != 1) {

2773 + if (nr_threads != 1 && record_ieot()) {

2774 int ieot_blocks, cpus;

2775

2776 /*