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Tweaked cache size to temporarily avoid pathological shrub overflows

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This will stop being a problem when we actually have btrees, but for now
the fragmentation caused by byte-level syncs was easily enough to
overflow an mdir when cache size is big.

A smaller cache size is also nicer for debugging, since smaller cache
sizes results in data getting flushed to disk earlier, which is easier
to inspect than in-device buffers. And a 16-byte cache still provides
decent test coverage over cache interactions.

---

Also dropped inline_size to block_size/8. I realized while debugging
that opened shrubs take up additional space until we sync, so we need to
expect up to 2 temporary copies of shrubs when writing files.
This commit is contained in:
Christopher Haster
2023-09-22 00:05:38 -05:00
parent 3fb4350ce7
commit 1d92169e5b
3 changed files with 8 additions and 5 deletions
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runners/bench_runner.h
+2 -2
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@@ -138,8 +138,8 @@ intmax_t bench_define(size_t define);
BENCH_DEF(BLOCK_SIZE, 0 ) \ BENCH_DEF(BLOCK_SIZE, 0 ) \
BENCH_DEF(BLOCK_COUNT, DISK_SIZE/BLOCK_SIZE ) \ BENCH_DEF(BLOCK_COUNT, DISK_SIZE/BLOCK_SIZE ) \
BENCH_DEF(DISK_SIZE, 1024*1024 ) \ BENCH_DEF(DISK_SIZE, 1024*1024 ) \
BENCH_DEF(CACHE_SIZE, lfs_max(64, lfs_max(READ_SIZE, PROG_SIZE))) \ BENCH_DEF(CACHE_SIZE, lfs_max(16, lfs_max(READ_SIZE, PROG_SIZE))) \
BENCH_DEF(INLINE_SIZE, BLOCK_SIZE/4 ) \ BENCH_DEF(INLINE_SIZE, BLOCK_SIZE/8 ) \
BENCH_DEF(BUD_SIZE, BLOCK_SIZE/4 ) \ BENCH_DEF(BUD_SIZE, BLOCK_SIZE/4 ) \
BENCH_DEF(LOOKAHEAD_SIZE, 16 ) \ BENCH_DEF(LOOKAHEAD_SIZE, 16 ) \
BENCH_DEF(BLOCK_CYCLES, -1 ) \ BENCH_DEF(BLOCK_CYCLES, -1 ) \
runners/test_runner.h
+2 -2
View File
@@ -137,8 +137,8 @@ intmax_t test_define(size_t define);
TEST_DEF(BLOCK_SIZE, 0 ) \ TEST_DEF(BLOCK_SIZE, 0 ) \
TEST_DEF(BLOCK_COUNT, DISK_SIZE/BLOCK_SIZE ) \ TEST_DEF(BLOCK_COUNT, DISK_SIZE/BLOCK_SIZE ) \
TEST_DEF(DISK_SIZE, 1024*1024 ) \ TEST_DEF(DISK_SIZE, 1024*1024 ) \
TEST_DEF(CACHE_SIZE, lfs_max(64, lfs_max(READ_SIZE, PROG_SIZE)) ) \ TEST_DEF(CACHE_SIZE, lfs_max(16, lfs_max(READ_SIZE, PROG_SIZE)) ) \
TEST_DEF(INLINE_SIZE, BLOCK_SIZE/4 ) \ TEST_DEF(INLINE_SIZE, BLOCK_SIZE/8 ) \
TEST_DEF(BUD_SIZE, BLOCK_SIZE/4 ) \ TEST_DEF(BUD_SIZE, BLOCK_SIZE/4 ) \
TEST_DEF(LOOKAHEAD_SIZE, 16 ) \ TEST_DEF(LOOKAHEAD_SIZE, 16 ) \
TEST_DEF(BLOCK_CYCLES, -1 ) \ TEST_DEF(BLOCK_CYCLES, -1 ) \
tests/test_ftree.toml
+4 -1
View File
@@ -510,6 +510,7 @@ code = '''
# write files incrementally # write files incrementally
[cases.test_ftree_incr] [cases.test_ftree_incr]
defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE'] defines.SIZE = ['CACHE_SIZE/2', '2*CACHE_SIZE']
defines.CHUNK = [4, 1]
defines.SYNC = [false, true] defines.SYNC = [false, true]
defines.REMOUNT = [false, true] defines.REMOUNT = [false, true]
reentrant = true reentrant = true
@@ -530,7 +531,9 @@ code = '''
uint32_t prng = 42; uint32_t prng = 42;
for (lfs_size_t i = 0; i < SIZE; i++) { for (lfs_size_t i = 0; i < SIZE; i++) {
wbuf[i] = 'a' + (TEST_PRNG(&prng) % 26); wbuf[i] = 'a' + (TEST_PRNG(&prng) % 26);
lfsr_file_write(&lfs, &file, &wbuf[i], 1) => 1; }
for (lfs_size_t i = 0; i < SIZE; i += CHUNK) {
lfsr_file_write(&lfs, &file, &wbuf[i], CHUNK) => CHUNK;
// sync? // sync?
if (SYNC) { if (SYNC) {