Cai Yudong

from the log, this issue may be duplicated with #18509, and should have been fixed in Milvus 2.1.2 ``` 2022-08-05T12:33:07+08:00 [2022/08/05 04:33:06.486 +00:00] [INFO] [querynode/reduce.go:155] ["purge memory done, memory was...

/assign @yanliang567 /unassign

@yanliang567 what's the index type and search param ?

test knowhere with sift1M dataset, till the last iteration (all data have been removed), knowhere can always return 10000 valid result. (bt means bitset count)  same...

[21785_create_n_insert.py.txt](https://github.com/milvus-io/milvus/files/10545663/21785_create_n_insert.py.txt) [21785_upsert.py.txt](https://github.com/milvus-io/milvus/files/10545664/21785_upsert.py.txt)

change metric type to "L2", script runs as expected 

do normalize with IP metric type, following script can always delete 10000 entities [21785_create_n_insert_normalize.py.txt](https://github.com/milvus-io/milvus/files/10552646/21785_create_n_insert_normalize.py.txt)

so this issue is not a real issue, IP metric type MUST do normalization first @yanliang567

/assign @yanliang567

> @cydrain Can you help do a further check on why this happens? Appreciate it! ok