add weakref to sync engine #1226
| Job | Run time |
|---|---|
| 2m 47s | |
| 6m 28s | |
| 2m 44s | |
| 6m 25s | |
| 6m 25s | |
| 14m 27s | |
| 6m 25s | |
| 5m 40s | |
| 6m 23s | |
| 14m 27s | |
| 6m 24s | |
| 8m 53s | |
| 6m 15s | |
| 14m 33s | |
| 6m 14s | |
| 6m 13s | |
| 6m 49s | |
| 14m 23s | |
| 6m 24s | |
| 6m 13s | |
| 2m 57s | |
| 11m 33s | |
| 4m 15s | |
| 4m 46s | |
| 3m 51s | |
| 12m 40s | |
| 4m 17s | |
| 4m 40s | |
| 3m 49s | |
| 11m 24s | |
| 3m 52s | |
| 4m 57s | |
| 3m 41s | |
| 13m 24s | |
| 3m 50s | |
| 4m 58s | |
| 4h 13m 26s |