Auto-generated documentation.
Perform a level/pebble db benchmark
polycli dbbench [flags]This command is meant to give us a sense of the system level performance for leveldb:
polycli dbbench --degree-of-parallelism 2 | jq '.' > result.jsonIn many cases, we'll want to emulate the performance characteristics
of bor or geth. This is the basic IO pattern when bor is in sync:
Process Name = bor
Kbytes : count distribution
0 -> 1 : 0 | |
2 -> 3 : 0 | |
4 -> 7 : 10239 |**************** |
8 -> 15 : 25370 |****************************************|
16 -> 31 : 7082 |*********** |
32 -> 63 : 1241 |* |
64 -> 127 : 58 | |
128 -> 255 : 11 | |
This is the IO pattern when bor is getting in sync.
Process Name = bor
Kbytes : count distribution
0 -> 1 : 0 | |
2 -> 3 : 0 | |
4 -> 7 : 23089 |************* |
8 -> 15 : 70350 |****************************************|
16 -> 31 : 11790 |****** |
32 -> 63 : 1193 | |
64 -> 127 : 204 | |
128 -> 255 : 271 | |
256 -> 511 : 1381 | |
This gives us a sense of the relative size of the IOPs. We'd also want to get a sense of the read/write ratio. This is some sample data from bor while syncing:
12:48:08 loadavg: 5.86 6.22 7.13 16/451 56297
READS WRITES R_Kb W_Kb PATH
307558 1277 4339783 30488 /var/lib/bor/data/bor/chaindata/
12:48:38 loadavg: 6.46 6.32 7.14 3/452 56298
READS WRITES R_Kb W_Kb PATH
309904 946 4399349 26051 /var/lib/bor/data/bor/chaindata/
During the same period of time this is what the IO looks like from a node that's in sync.
12:48:05 loadavg: 1.55 1.85 2.03 18/416 88371
READS WRITES R_Kb W_Kb PATH
124530 488 1437436 12165 /var/lib/bor/data/bor/chaindata/
12:48:35 loadavg: 4.14 2.44 2.22 1/416 88371
READS WRITES R_Kb W_Kb PATH
81282 215 823530 4610 /var/lib/bor/data/bor/chaindata/
If we want to simulate bor behavior, we can leverage this data to
configure the leveldb benchmark tool.
| Syncing | Reads | Writes | Read (kb) | Write (kb) | RW Ratio | kb/r | kb/w |
|---|---|---|---|---|---|---|---|
| TRUE | 307,558 | 1,277 | 4,339,783 | 30,488 | 241 | 14.1 | 23.9 |
| TRUE | 309,904 | 946 | 7,399,349 | 26,051 | 328 | 23.9 | 27.5 |
| FALSE | 124,530 | 488 | 1,437,436 | 12,165 | 255 | 11.5 | 24.9 |
| FALSE | 51,282 | 215 | 823,530 | 4,610 | 239 | 16.1 | 21.4 |
The number of IOps while syncing is a lot higher. The only other obvious difference is that the IOp size is a bit larger while syncing as well.
- Syncing
- Read Write Ratio - 275:1
- Small IOp - 10kb
- Large IOp - 256kb
- Small Large Ratio - 10:1
- Synced
- Read Write Ratio - 250:1
- Small IOp - 10kb
- Large IOp - 32kb
- Small Large Ratio - 10:1
7:58PM DBG buckets bucket=0 count=9559791821 end=1 start=0
7:58PM DBG buckets bucket=1 count=141033 end=3 start=2
7:58PM DBG buckets bucket=2 count=92899 end=7 start=4
7:58PM DBG buckets bucket=3 count=256655 end=15 start=8
7:58PM DBG buckets bucket=4 count=262589 end=31 start=16
7:58PM DBG buckets bucket=5 count=191353 end=63 start=32
7:58PM DBG buckets bucket=6 count=99519 end=127 start=64
7:58PM DBG buckets bucket=7 count=74161 end=255 start=128
7:58PM DBG buckets bucket=8 count=17426 end=511 start=256
7:58PM DBG buckets bucket=9 count=692 end=1023 start=512
7:58PM DBG buckets bucket=10 count=989 end=2047 start=1024
7:58PM DBG buckets bucket=13 count=1 end=16383 start=8192
7:58PM INF recorded result desc="full scan" testDuration=10381196.479925
7:58PM DBG recorded result result={"Description":"full scan","EndTime":"2023-07-17T19:58:05.396257711Z","OpCount":9557081144,"OpRate":920614.609547304,"StartTime":"2023-07-17T17:05:04.199777776Z","Stats":{"AliveIterators":0,"AliveSnapshots":0,"BlockCache":{"Buckets":2048,"DelCount":259134854,"GrowCount":9,"HitCount":4,"MissCount":262147633,"Nodes":33294,"SetCount":259168148,"ShrinkCount":2,"Size":268427343},"BlockCacheSize":268427343,"FileCache":{"Buckets":16,"DelCount":536037,"GrowCount":0,"HitCount":2,"MissCount":536537,"Nodes":500,"SetCount":536537,"ShrinkCount":0,"Size":500},"IORead":1092651461848,"IOWrite":13032122717,"Level0Comp":0,"LevelDurations":[0,0,546151937,15675194130,100457643600,40581548153,0],"LevelRead":[0,0,45189458,1233235440,8351239571,3376108236,0],"LevelSizes":[0,103263963,1048356844,10484866671,104856767171,180600915234,797187827055],"LevelTablesCounts":[0,51,665,7066,53522,95777,371946],"LevelWrite":[0,0,45159786,1230799439,8328970986,3371359447,0],"MemComp":0,"NonLevel0Comp":1433,"OpenedTablesCount":500,"SeekComp":0,"WriteDelayCount":0,"WriteDelayDuration":0,"WritePaused":false},"TestDuration":10381196479925,"ValueDist":null}
--cache-size int the number of megabytes to use as our internal cache size (default 512)
--db-mode string The mode to use: leveldb or pebbledb (default "leveldb")
--db-path string the path of the database that we'll use for testing (default "_benchmark_db")
--degree-of-parallelism uint8 The number of concurrent goroutines we'll use (default 2)
--dont-fill-read-cache if false, then random reads will be cached
--full-scan-mode if true, the application will scan the full database as fast as possible and print a summary
--handles int defines the capacity of the open files caching. Use -1 for zero, this has same effect as specifying NoCacher to OpenFilesCacher. (default 500)
-h, --help help for dbbench
--key-size uint The byte length of the keys that we'll use (default 32)
--nil-read-opts if true we'll use nil read opt (this is what geth/bor does)
--no-merge-write allows disabling write merge
--overwrite-count uint the number of times to overwrite the data (default 5)
--read-limit uint the number of reads will attempt to complete in a given test (default 10000000)
--read-only if true, we'll skip all the write operations and open the DB in read only mode
--read-strict if true the rand reads will be made in strict mode
--sequential-reads if true we'll perform reads sequentially
--sequential-writes if true we'll perform writes in somewhat sequential manner
--size-distribution string the size distribution to use while testing (default "0-1:2347864,2-3:804394856,4-7:541267689,8-15:738828593,16-31:261122372,32-63:1063470933,64-127:3584745195,128-255:1605760137,256-511:316074206,512-1023:312887514,1024-2047:328894149,2048-4095:141180,4096-8191:92789,8192-16383:256060,16384-32767:261806,32768-65535:191032,65536-131071:99715,131072-262143:73782,262144-524287:17552,524288-1048575:717,1048576-2097151:995,2097152-4194303:1,8388608-16777215:1")
--sync-writes sync each write
--write-limit uint The number of entries to write in the db (default 1000000)
--write-zero if true, we'll write 0s rather than random dataThe command also inherits flags from parent commands.
--config string config file (default is $HOME/.polygon-cli.yaml)
--pretty-logs Should logs be in pretty format or JSON (default true)
-v, --verbosity int 0 - Silent
100 Panic
200 Fatal
300 Error
400 Warning
500 Info
600 Debug
700 Trace (default 500)- polycli - A Swiss Army knife of blockchain tools.