Open GoogleCodeExporter opened 9 years ago
This show how it happens:
Compactions
Level Files Size(MB) Time(sec) Read(MB) Write(MB)
--------------------------------------------------
0 0 0 0 0 11
2 1 39 2 0 118
3 0 0 2 90 88
4 386 10062 354 30228 30227
5 1798 53047 1897 158227 158183
Compactions
Level Files Size(MB) Time(sec) Read(MB) Write(MB)
--------------------------------------------------
0 0 0 0 0 11
2 0 0 2 0 118
3 32 39 2 130 127
4 386 10062 354 30228 30227
5 1798 53047 1897 158227 158183
Compactions
Level Files Size(MB) Time(sec) Read(MB) Write(MB)
--------------------------------------------------
0 0 0 0 0 11
2 0 0 2 0 118
3 29 3 2 130 127
4 542 10092 361 30850 30849
5 1798 53049 1919 159486 159440
Original comment by wuzuy...@gmail.com
on 15 May 2013 at 5:08
I see this line in leveldb doc:
```We also switch to a new output file when the key range of the current output
file has grown enough to overlap more then ten level-(L+2) files.```
I assume that the only file in level-2 overlaps many files in level-4, so it
splits into 32 level-3 files. I don't think this mechanism is good, because
later Get() operations will force seek_compactions on all these level-3 files
to be merged with level-4 files.
Original comment by wuzuy...@gmail.com
on 15 May 2013 at 5:39
I believe I'm seeing this too.
... 270 small files created
03:13:21.412464 Generated table #1073824: 13 keys, 7209 bytes
03:13:21.504346 Generated table #1073825: 15 keys, 8345 bytes
03:13:21.597557 Generated table #1073826: 4 keys, 2437 bytes
03:13:21.679429 Generated table #1073827: 9 keys, 4581 bytes
03:13:21.771315 Generated table #1073828: 6 keys, 2784 bytes
03:13:21.853079 Generated table #1073829: 12 keys, 5856 bytes
03:13:21.934807 Generated table #1073830: 10 keys, 13350 bytes
03:13:22.016480 Generated table #1073831: 11 keys, 6459 bytes
03:13:22.108478 Generated table #1073832: 10 keys, 5504 bytes
03:13:22.200398 Generated table #1073833: 17 keys, 17318 bytes
03:13:22.282151 Generated table #1073834: 13 keys, 23513 bytes
03:13:22.384259 Generated table #1073835: 9 keys, 4937 bytes
03:13:22.466041 Generated table #1073836: 7 keys, 3846 bytes
03:13:22.547809 Generated table #1073837: 18 keys, 25082 bytes
03:13:22.547833 Compacted 1@2 + 16@3 files => 16725003 bytes
03:13:22.629348 compacted to: files[ 0 0 36 682 5304 359 0 ]
03:13:22.640214 Delete type=2 #1073495
03:13:22.640276 Delete type=2 #1073500
03:13:22.640396 Delete type=2 #1073503
03:13:22.640439 Delete type=2 #1073501
03:13:22.640615 Delete type=2 #1073505
03:13:22.640873 Delete type=2 #1073511
03:13:22.640966 Delete type=2 #1073502
03:13:22.641269 Delete type=2 #1073506
03:13:22.641372 Delete type=2 #1073508
03:13:22.641434 Delete type=2 #1073493
03:13:22.641488 Delete type=2 #1073512
03:13:22.641619 Delete type=2 #1073528
03:13:22.641658 Delete type=2 #1073494
...
Original comment by DavidJoelSchwartz@gmail.com
on 17 May 2013 at 1:23
Original issue reported on code.google.com by
wuzuy...@gmail.com
on 15 May 2013 at 2:08