feat: using client-side streaming and avoiding read lock to optimize raft message sending

[MrCroxx]

Changes:

• Use client-side streaming grpc to reduce raft send messages latency.
• Raft worker get raft clients when init to avoid read lock when sending raft messages.

Summary:

• Raft send messages latency gains barely nothing from client-side streaming grpc or avoiding read lock (Maybe the messages batch is small? Need metrics to further investigate).
• Avoiding read lock benefits the serivce latency.

Ref: #126 .

[MrCroxx]

main cf3415d:

[codecov[bot]]

Codecov Report

Merging #134 (401f29d) into main (cf3415d) will increase coverage by 0.20%. The diff coverage is 91.13%.

:exclamation: Current head 401f29d differs from pull request most recent head 5f95042. Consider uploading reports for the commit 5f95042 to get more accurate results

@@            Coverage Diff             @@
##             main     #134      +/-   ##
==========================================
+ Coverage   82.20%   82.41%   +0.20%     
==========================================
  Files          74       75       +1     
  Lines        7273     7272       -1     
==========================================
+ Hits         5979     5993      +14     
+ Misses       1294     1279      -15     

Impacted Files	Coverage Δ
client/src/lib.rs	50.00% <50.00%> (ø)
wheel/src/components/raft_network.rs	86.11% <91.42%> (-1.87%)	:arrow_down:
wheel/src/service.rs	78.57% <92.30%> (+3.94%)	:arrow_up:
wheel/src/worker/raft.rs	86.98% <93.10%> (+0.30%)	:arrow_up:
storage/src/lsm_tree/components/skiplist/list.rs	85.44% <0.00%> (-0.32%)	:arrow_down:
storage/src/lsm_tree/manifest/version.rs	82.10% <0.00%> (+0.22%)	:arrow_up:
wheel/src/components/fsm.rs	68.52% <0.00%> (+0.50%)	:arrow_up:
... and 1 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more Δ = absolute <relative> (impact), ø = not affected, ? = missing data Powered by Codecov. Last update cf3415d...5f95042. Read the comment docs.

[MrCroxx]

0635bb5 (worser?):

[MrCroxx]

HEAD 401f29d:

[MrCroxx]

A little relief: integration tests runs really faster than before (40s+ -> 30s-, 10s+ preparation included).

[MrCroxx]

Thought twice, it seems that I used client-side streaming grpc in a wrong way. Try later.