fix: improve lock and sync when calling and trimming by dordsor21 · Pull Request #3543 · IntellectualSites/FastAsyncWorldEdit

dordsor21 · 2026-05-24T13:21:09Z

also fix error when editing newly generated chunks due to postprocessgen not having been completed
fixes Plugin "stopping" to work. #3490

PierreSchwang

Untested, but looks reasonable so far

SirYwell · 2026-05-25T18:08:33Z

+            fieldPendingBlockEntities = ChunkAccess.class.getDeclaredField(Refraction.pickName(
+                            "pendingBlockEntities",
+                            "i"
+                    )
+            );


There shouldn't be any obfuscation anymore, right?

No idea, I was just going along with everything... If it's been removed we can clean up a bunch of this class I guess? (This field is both paper and spigot fwiw)

- also fix error when editing newly generated chunks due to postprocessgen not having been completed - fixes #3490

MattBDev · 2026-08-04T16:13:48Z

Code review

Found 2 issues. Both are single-adapter divergences — a change applied correctly to 7 of the 8 per-version copies, missed in the 8th.

Lock-order inversion in adapter-26.2 only. internalCall now enters synchronized (this) before taking sectionLock.writeLock(), but trim(true) in the same file takes sectionLock.writeLock() first and then synchronized (this). That is an AB-BA inversion between an edit thread and cache trimming — the exact interaction this PR is meant to fix. The base revision had no synchronized (this) here at all, so the PR introduces it.

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-26.2/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_2/PaperweightGetBlocks.java

Lines 536 to 540 in 45c46ae

    
           try { 
        
               synchronized (this) { 
        
                   sectionLock.writeLock().lock(); 
        
                   if (this.getChunk() != nmsChunk) { 
        
                       this.levelChunk = nmsChunk;

Opposite order in trim(boolean aggressive) in the same file:

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-26.2/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_2/PaperweightGetBlocks.java

Lines 1051 to 1056 in 45c46ae

    
           if (aggressive) { 
        
               sectionLock.writeLock().lock(); 
        
               try { 
        
                   synchronized (this) { 
        
                       skyLight = new DataLayer[getSectionCount()]; 
        
                       blockLight = new DataLayer[getSectionCount()];

The other seven adapters lock in the order that matches their own trim(), e.g. adapter-26.1:

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-26.1/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_1/PaperweightGetBlocks.java

Lines 534 to 538 in 45c46ae

    
           try { 
        
               sectionLock.writeLock().lock(); 
        
               synchronized (this) { 
        
                   if (this.getChunk() != nmsChunk) { 
        
                       this.levelChunk = nmsChunk;

adapter-1_21 is missing the boolean createCopy = this.createCopy; snapshot that the other seven adapters gained in this PR. copy is decided once from the field, but the deferred syncTasks lambda re-reads the live, non-volatile AbstractBukkitGetBlocks.createCopy when it later runs on the sync thread. If setCreateCopy flips the field in between, createCopy reads true while copy is still null, NPE-ing on copy.storeEntity(entity).

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-1_21/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_R1/PaperweightGetBlocks.java

Lines 339 to 343 in 45c46ae

    
           ) throws Exception { 
        
               Map<BlockPos, CompoundTag> tilesToInit = PaperweightPlatformAdapter.clearPostProcessing(nmsChunk, false); 
        
               PaperweightGetBlocks_Copy copy = createCopy ? new PaperweightGetBlocks_Copy(nmsChunk) : null; 
        
               if (createCopy) { 
        
                   if (copies.containsKey(copyKey)) {

Deferred read of the live field:

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-1_21/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_R1/PaperweightGetBlocks.java

Lines 632 to 636 in 45c46ae

    
           if (entityRemoves.contains(uuid)) { 
        
               if (createCopy) { 
        
                   copy.storeEntity(entity); 
        
               } 
        
               removeEntity(entity);

Compare adapter-1_21_11, which has the snapshot:

FastAsyncWorldEdit/worldedit-bukkit/adapters/adapter-1_21_11/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_11/PaperweightGetBlocks.java

Lines 336 to 338 in 45c46ae

    
           Map<BlockPos, CompoundTag> tilesToInit = PaperweightPlatformAdapter.clearPostProcessing(nmsChunk, false); 
        
           boolean createCopy = this.createCopy; 
        
           PaperweightGetBlocks_Copy copy = createCopy ? new PaperweightGetBlocks_Copy(nmsChunk) : null;

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Copilot

Pull request overview

This PR focuses on improving concurrency/locking behavior during chunk “call” execution and trimming, and adds handling for editing chunks that are newly generated but have not completed post-processing (pending block entity initialization), addressing issue #3490.

Changes:

Adjust chunk GET call synchronization/visibility behavior in the shared Bukkit adapter base.
Add logic across multiple Paperweight adapters to temporarily manage pendingBlockEntities during edits when post-processing hasn’t completed.
Refactor sync-task construction and trim logic in multiple versioned adapters.

Reviewed changes

Copilot reviewed 17 out of 17 changed files in this pull request and generated 7 comments.

Show a summary per file

File	Description
worldedit-bukkit/src/main/java/com/fastasyncworldedit/bukkit/adapter/AbstractBukkitGetBlocks.java	Removes `synchronized` from `call()` (relying on `callLock`) and makes `forceLoadSections` `volatile` for cross-thread visibility.
worldedit-bukkit/adapters/adapter-26.2/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_2/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-26.2/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_2/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-26.1/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_1/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-26.1/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v26_1/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-1_21/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_R1/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_R1/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction and trim logic.
worldedit-bukkit/adapters/adapter-1_21_9/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_9/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21_9/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_9/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-1_21_6/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_6/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21_6/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_6/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-1_21_5/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_5/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21_5/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_5/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-1_21_4/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_4/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21_4/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_4/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; adjusts trimming flow.
worldedit-bukkit/adapters/adapter-1_21_11/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_11/PaperweightPlatformAdapter.java	Adds reflective accessors to clear/restore `pendingBlockEntities` for post-processing handling.
worldedit-bukkit/adapters/adapter-1_21_11/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/fawe/v1_21_11/PaperweightGetBlocks.java	Uses new post-processing helpers; refactors sync task construction; includes corrected trim section-index mapping.

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+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


+            }
+        }
+        return true;
    }

 }


+        for (int i = 0; i < trim.length; i++) {
+            if (trim[i]) {
+                super.trim(false, i);
+            }
+        }


dordsor21 requested a review from a team as a code owner May 24, 2026 13:21

PierreSchwang approved these changes May 25, 2026

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SirYwell requested changes May 25, 2026

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dordsor21 requested a review from SirYwell May 31, 2026 08:56

SirYwell mentioned this pull request Jun 18, 2026

Remove block entities on server thread #3564

Open

4 tasks

dordsor21 added 3 commits July 25, 2026 14:32

fix: improve lock and sync when calling and trimming

8900f89

- also fix error when editing newly generated chunks due to postprocessgen not having been completed - fixes #3490

not obf

6d805ad

add for 26.2

45c46ae

dordsor21 force-pushed the fiix/call-trim-deadlock branch from a6a08b7 to 45c46ae Compare July 25, 2026 15:31

dordsor21 requested a review from a team July 26, 2026 11:12

MattBDev mentioned this pull request Aug 5, 2026

Run edit-completion tasks on a dedicated executor #3609

Open

address comments

44722c1

MattBDev approved these changes Aug 11, 2026

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NotMyFault requested a lite review from Copilot August 14, 2026 18:32

Copilot started reviewing on behalf of NotMyFault August 14, 2026 18:32 View session

Copilot AI reviewed Aug 14, 2026

View reviewed changes

fix trim calls

cb6d671

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fix: improve lock and sync when calling and trimming - #3543

fix: improve lock and sync when calling and trimming#3543
dordsor21 wants to merge 5 commits into
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