## Proposed changes
Do `load_cache_info_into_memory()` asynchronously in a background thread
in `LRUFileCache::initialize()`.
When the cache is not ready, `LRUFileCache::get_or_set()` will return
the FileBlock which state is SKIP_CACHE.
pick https://github.com/apache/doris/pull/37062
1. revert https://github.com/apache/doris/pull/25097. we decide to rely
on OS. not maintain independent tzdata anymore to keep result
consistency
2. refactor timezone load. removed rwlock.
before:
```sql
mysql [optest]>select count(convert_tz(d, 'Asia/Shanghai', 'America/Los_Angeles')), count(convert_tz(dt, 'America/Los_Angeles', '+00:00')) from dates;
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
| count(convert_tz(cast(d as DATETIMEV2(6)), 'Asia/Shanghai', 'America/Los_Angeles')) | count(convert_tz(dt, 'America/Los_Angeles', '+00:00')) |
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
| 16000000 | 16000000 |
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
1 row in set (6.88 sec)
```
now:
```sql
mysql [optest]>select count(convert_tz(d, 'Asia/Shanghai', 'America/Los_Angeles')), count(convert_tz(dt, 'America/Los_Angeles', '+00:00')) from dates;
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
| count(convert_tz(cast(d as DATETIMEV2(6)), 'Asia/Shanghai', 'America/Los_Angeles')) | count(convert_tz(dt, 'America/Los_Angeles', '+00:00')) |
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
| 16000000 | 16000000 |
+-------------------------------------------------------------------------------------+--------------------------------------------------------+
1 row in set (2.61 sec)
```
3. now don't support timezone offset format string like 'UTC+8', like we
already said in
https://doris.apache.org/docs/dev/query/query-variables/time-zone/#usage
4. support case-insensitive timezone parsing in nereids.
5. a bug when parse timezone using nereids. should check DST by input,
but wrongly by now before. now fixed.
doc pr: https://github.com/apache/doris-website/pull/810
bp #36045, and turn on batch split, which is turn off in #36109
Generate and get split batch concurrently.
`SplitSource.getNextBatch` remove the synchronization, and make each get their splits concurrently, and `SplitAssignment` generates splits asynchronously.
- Add 2 new BE config
- `s3_read_base_wait_time_ms` and `s3_read_max_wait_time_ms`
When meet s3 429 error, the "get" request will
sleep `s3_read_base_wait_time_ms (*1, *2, *3, *4)` ms get try again.
The max sleep time is s3_read_max_wait_time_ms
and the max retry time is max_s3_client_retry
- Add more metrics for s3 file reader
- `s3_file_reader_too_many_request`: counter of 429 error.
- `s3_file_reader_s3_get_request`: the QPS of s3 get request.
- `TotalGetRequest`: Get request counter in profile
- `TooManyRequestErr`: 429 error counter in profile
- `TooManyRequestSleepTime`: Sum of sleep time after 429 error in profile
- `TotalBytesRead`: Total bytes read from s3 in profile
## Proposed changes
Issue Number: close #xxx
<!--Describe your changes.-->
## Further comments
If this is a relatively large or complex change, kick off the discussion
at [dev@doris.apache.org](mailto:dev@doris.apache.org) by explaining why
you chose the solution you did and what alternatives you considered,
etc...
1. `memory.usage_in_bytes ~= free.used + free.(buff/cache) - (buff)`, free cache can be reused,
so, modify cgroup_memory_usage = memory.usage_in_bytes - memory.meminfo["Cached"].
2. If system not configured with cgroup, find cgroup file path will failed, refactor refresh cgroup memory info, compatible with find failed.
