fix & perf: stats compute string len stats only for strings
#6553
| Job | Run time |
|---|---|
| 14m 32s | |
| 14m 38s | |
| 29m 10s |
stats compute string len stats only for strings
#6553
| Job | Run time |
|---|---|
| 14m 32s | |
| 14m 38s | |
| 29m 10s |