mirror of
https://github.com/git/git
synced 2024-07-02 15:48:44 +00:00
refs/reftable: allow configuring block size
Add a new option `reftable.blockSize` that allows the user to control the block size used by the reftable library. Signed-off-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
parent
fcf341890e
commit
831b366c24
|
@ -498,6 +498,8 @@ include::config/rebase.txt[]
|
|||
|
||||
include::config/receive.txt[]
|
||||
|
||||
include::config/reftable.txt[]
|
||||
|
||||
include::config/remote.txt[]
|
||||
|
||||
include::config/remotes.txt[]
|
||||
|
|
14
Documentation/config/reftable.txt
Normal file
14
Documentation/config/reftable.txt
Normal file
|
@ -0,0 +1,14 @@
|
|||
reftable.blockSize::
|
||||
The size in bytes used by the reftable backend when writing blocks.
|
||||
The block size is determined by the writer, and does not have to be a
|
||||
power of 2. The block size must be larger than the longest reference
|
||||
name or log entry used in the repository, as references cannot span
|
||||
blocks.
|
||||
+
|
||||
Powers of two that are friendly to the virtual memory system or
|
||||
filesystem (such as 4kB or 8kB) are recommended. Larger sizes (64kB) can
|
||||
yield better compression, with a possible increased cost incurred by
|
||||
readers during access.
|
||||
+
|
||||
The largest block size is `16777215` bytes (15.99 MiB). The default value is
|
||||
`4096` bytes (4kB). A value of `0` will use the default value.
|
|
@ -1,6 +1,7 @@
|
|||
#include "../git-compat-util.h"
|
||||
#include "../abspath.h"
|
||||
#include "../chdir-notify.h"
|
||||
#include "../config.h"
|
||||
#include "../environment.h"
|
||||
#include "../gettext.h"
|
||||
#include "../hash.h"
|
||||
|
@ -228,6 +229,22 @@ static int read_ref_without_reload(struct reftable_stack *stack,
|
|||
return ret;
|
||||
}
|
||||
|
||||
static int reftable_be_config(const char *var, const char *value,
|
||||
const struct config_context *ctx,
|
||||
void *_opts)
|
||||
{
|
||||
struct reftable_write_options *opts = _opts;
|
||||
|
||||
if (!strcmp(var, "reftable.blocksize")) {
|
||||
unsigned long block_size = git_config_ulong(var, value, ctx->kvi);
|
||||
if (block_size > 16777215)
|
||||
die("reftable block size cannot exceed 16MB");
|
||||
opts->block_size = block_size;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct ref_store *reftable_be_init(struct repository *repo,
|
||||
const char *gitdir,
|
||||
unsigned int store_flags)
|
||||
|
@ -243,12 +260,24 @@ static struct ref_store *reftable_be_init(struct repository *repo,
|
|||
base_ref_store_init(&refs->base, repo, gitdir, &refs_be_reftable);
|
||||
strmap_init(&refs->worktree_stacks);
|
||||
refs->store_flags = store_flags;
|
||||
refs->write_options.block_size = 4096;
|
||||
|
||||
refs->write_options.hash_id = repo->hash_algo->format_id;
|
||||
refs->write_options.default_permissions = calc_shared_perm(0666 & ~mask);
|
||||
refs->write_options.disable_auto_compact =
|
||||
!git_env_bool("GIT_TEST_REFTABLE_AUTOCOMPACTION", 1);
|
||||
|
||||
git_config(reftable_be_config, &refs->write_options);
|
||||
|
||||
/*
|
||||
* It is somewhat unfortunate that we have to mirror the default block
|
||||
* size of the reftable library here. But given that the write options
|
||||
* wouldn't be updated by the library here, and given that we require
|
||||
* the proper block size to trim reflog message so that they fit, we
|
||||
* must set up a proper value here.
|
||||
*/
|
||||
if (!refs->write_options.block_size)
|
||||
refs->write_options.block_size = 4096;
|
||||
|
||||
/*
|
||||
* Set up the main reftable stack that is hosted in GIT_COMMON_DIR.
|
||||
* This stack contains both the shared and the main worktree refs.
|
||||
|
|
|
@ -99,4 +99,76 @@ test_expect_success 'many refs results in multiple blocks' '
|
|||
)
|
||||
'
|
||||
|
||||
test_expect_success 'tiny block size leads to error' '
|
||||
test_when_finished "rm -rf repo" &&
|
||||
git init repo &&
|
||||
(
|
||||
cd repo &&
|
||||
test_commit initial &&
|
||||
cat >expect <<-EOF &&
|
||||
error: unable to compact stack: entry too large
|
||||
EOF
|
||||
test_must_fail git -c reftable.blockSize=50 pack-refs 2>err &&
|
||||
test_cmp expect err
|
||||
)
|
||||
'
|
||||
|
||||
test_expect_success 'small block size leads to multiple ref blocks' '
|
||||
test_config_global core.logAllRefUpdates false &&
|
||||
test_when_finished "rm -rf repo" &&
|
||||
git init repo &&
|
||||
(
|
||||
cd repo &&
|
||||
test_commit A &&
|
||||
test_commit B &&
|
||||
git -c reftable.blockSize=100 pack-refs &&
|
||||
|
||||
cat >expect <<-EOF &&
|
||||
header:
|
||||
block_size: 100
|
||||
ref:
|
||||
- length: 53
|
||||
restarts: 1
|
||||
- length: 74
|
||||
restarts: 1
|
||||
- length: 38
|
||||
restarts: 1
|
||||
EOF
|
||||
test-tool dump-reftable -b .git/reftable/*.ref >actual &&
|
||||
test_cmp expect actual
|
||||
)
|
||||
'
|
||||
|
||||
test_expect_success 'small block size fails with large reflog message' '
|
||||
test_when_finished "rm -rf repo" &&
|
||||
git init repo &&
|
||||
(
|
||||
cd repo &&
|
||||
test_commit A &&
|
||||
perl -e "print \"a\" x 500" >logmsg &&
|
||||
cat >expect <<-EOF &&
|
||||
fatal: update_ref failed for ref ${SQ}refs/heads/logme${SQ}: reftable: transaction failure: entry too large
|
||||
EOF
|
||||
test_must_fail git -c reftable.blockSize=100 \
|
||||
update-ref -m "$(cat logmsg)" refs/heads/logme HEAD 2>err &&
|
||||
test_cmp expect err
|
||||
)
|
||||
'
|
||||
|
||||
test_expect_success 'block size exceeding maximum supported size' '
|
||||
test_config_global core.logAllRefUpdates false &&
|
||||
test_when_finished "rm -rf repo" &&
|
||||
git init repo &&
|
||||
(
|
||||
cd repo &&
|
||||
test_commit A &&
|
||||
test_commit B &&
|
||||
cat >expect <<-EOF &&
|
||||
fatal: reftable block size cannot exceed 16MB
|
||||
EOF
|
||||
test_must_fail git -c reftable.blockSize=16777216 pack-refs 2>err &&
|
||||
test_cmp expect err
|
||||
)
|
||||
'
|
||||
|
||||
test_done
|
||||
|
|
Loading…
Reference in New Issue
Block a user