fix(scale): fix serving fragment bitmap for scale

[chenzl25]

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What's changed and what's your intention?

• Solve bug: Scale doesn't notify the new distribution to frontend  #13349

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[codecov]

Codecov Report

Merging #13395 (53a0547) into main (950ed58) will increase coverage by 0.05%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##             main   #13395      +/-   ##
==========================================
+ Coverage   67.81%   67.87%   +0.05%     
==========================================
  Files        1526     1526              
  Lines      259803   259843      +40     
==========================================
+ Hits       176197   176372     +175     
+ Misses      83606    83471     -135     

Flag	Coverage Δ
rust	67.87% <0.00%> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files	Coverage Δ
src/meta/src/serving/mod.rs	0.00% <0.00%> (ø)
src/meta/src/stream/scale.rs	10.24% <0.00%> (-0.27%)	⬇️

... and 16 files with indirect coverage changes

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[shanicky]

risingwave/src/meta/src/manager/catalog/fragment.rs

Line 1115 in aaccc89

for mapping in fragment_mapping_to_notify {

Did the mapping update here (in post_apply_reschedules) not take effect? 🤔

[chenzl25]

risingwave/src/meta/src/manager/catalog/fragment.rs

Line 1115 in aaccc89

for mapping in fragment_mapping_to_notify {

Did the mapping update here (in post_apply_reschedules) not take effect? 🤔

IIRC, @zwang28 had introduced a ServingParallelUnitMappings which is different from ParallelUnitMapping (for streaming). We need to notify changed ServingParallelUnitMappings to the frontend as well.

[zwang28]

LGTM. Thanks.

[zwang28]

FYI you can check serving vnode mapping in risectl. #10331
@chenzl25