Question

我有一个监听器附加到Firebase密钥，该密钥接受更改，通过我的处理运行它，然后使用结果更新Firebase密钥。代码如下所示：

db.child(key).on('child_added', (snap) => {
  processing(snap.val())
    .then([snapKey, obj] => db.child(snapKey).update(obj))
});

但是，当我注意到每次在Firebase密钥上调用更新时，内存使用量会泄漏几兆字节，这是不可接受的。

当我使用来自memwatch-next的探测时，这就是我的代码：

db.child(key).on('child_added', (snap) => {
  processing(snap.val())
    .then([snapKey, firebaseObj]) => {
      return new Promise((res) => {
        hd = new memwatch.HeapDiff();
        db.child(key).child(snapKey).update(firebaseObj, () => {
          res(hd);
        })
      })
    })
    .then((hd) => {
      console.log(hd.end());
    })
});

这是我运行代码时console.log(hd.end())行返回的几次迭代（每次迭代都在添加的每个子节点中）：

{ before: { nodes: 146168, size_bytes: 17594735, size: '16.78 mb' },
  after: { nodes: 176255, size_bytes: 19080111, size: '18.2 mb' },
  change: 
  { size_bytes: 1485376,
    size: '1.42 mb',
    freed_nodes: 5187,
    allocated_nodes: 35274,
    details: 
    [ [Object],
      ...
      [Object] ] } }

{ before: { nodes: 178862, size_bytes: 19198176, size: '18.31 mb' },
  after: { nodes: 212089, size_bytes: 20877626, size: '19.91 mb' },
  change: 
  { size_bytes: 1679450,
    size: '1.6 mb',
    freed_nodes: 1471,
    allocated_nodes: 34699,
    details: 
     [ [Object],
       ...
       [Object] ] } }

{ before: { nodes: 214254, size_bytes: 20919620, size: '19.95 mb' },
  after: { nodes: 247320, size_bytes: 22549300, size: '21.5 mb' },
  change: 
   { size_bytes: 1629680,
     size: '1.55 mb',
     freed_nodes: 1404,
     allocated_nodes: 34471,
     details: 
      [ [Object],
        ...
    [Object] ] } }

{ before: { nodes: 249507, size_bytes: 22614374, size: '21.57 mb' },
  after: { nodes: 282578, size_bytes: 24219130, size: '23.1 mb' },
  change: 
   { size_bytes: 1604756,
     size: '1.53 mb',
     freed_nodes: 1390,
     allocated_nodes: 34462,
     details: 
      [ [Object],
        ...
        [Object] ] } }

{ before: { nodes: 284930, size_bytes: 24329463, size: '23.2 mb' },
  after: { nodes: 317934, size_bytes: 25917780, size: '24.72 mb' },
  change: 
   { size_bytes: 1588317,
     size: '1.51 mb',
     freed_nodes: 1400,
     allocated_nodes: 34405,
     details: 
      [ [Object],
        ...
        [Object] ] } }

由于这种泄漏，在运行我的节点应用程序时，我遇到了这个错误：

Error: spawn ENOMEM
at _errnoException (util.js:999:13)
at ChildProcess.spawn (internal/child_process.js:340:11)
at exports.spawn (child_process.js:499:9)
at Object.exports.fork (child_process.js:100:10)
at rateLimit (/home/deploy/amNewBack/releases/20180104233801/index.js:118:33)
at ChildProcess.n.on 
(/home/deploy/amNewBack/releases/20180104233801/index.js:143:15)
at ChildProcess.emit (events.js:159:13)
at emit (internal/child_process.js:790:12)
at process._tickCallback (internal/process/next_tick.js:152:19)
FATAL ERROR: Committing semi space failed. Allocation failed - process out of         
memory
1: node::Abort() [/usr/local/bin/node]
2: 0x11ef43c [/usr/local/bin/node]
3: v8::Utils::ReportOOMFailure(char const*, bool) [/usr/local/bin/node]
4: v8::internal::V8::FatalProcessOutOfMemory(char const*, bool) 
[/usr/local/bin/node]
5: 
v8::internal::Heap::PerformGarbageCollection(v8::internal::GarbageCollector, 
v8::GCCallbackFlags) [/usr/local/bin/node]
6: v8::internal::Heap::CollectGarbage(v8::internal::AllocationSpace, 
v8::internal::GarbageCollectionReason, v8::GCCallbackFlags) 
[/usr/local/bin/node]
7: v8::internal::Factory::NewRawTwoByteString(int, 
v8::internal::PretenureFlag) 
[/usr/local/bin/node]
8: v8::internal::Factory::NewStringFromUtf8(v8::internal::Vector<char const>, 
 v8::internal::PretenureFlag) [/usr/local/bin/node]
9: v8::String::NewFromUtf8(v8::Isolate*, char const*, v8::NewStringType, int) 
 [/usr/local/bin/node]
10: node::StringBytes::Encode(v8::Isolate*, char const*, unsigned long, 
 node::encoding, v8::Local<v8::Value>*) [/usr/local/bin/node]
11: 0x120b762 [/usr/local/bin/node]
12: v8::internal::FunctionCallbackArguments::Call(void (*)
 (v8::FunctionCallbackInfo<v8::Value> const&)) [/usr/local/bin/node]
13: 0xb7c08c [/usr/local/bin/node]
14: v8::internal::Builtin_HandleApiCall(int, v8::internal::Object**,     
 v8::internal::Isolate*) [/usr/local/bin/node]
15: 0x326bb34842fd
FATAL ERROR: Deoptimizer::EnsureCodeForDeoptimizationEntry Allocation failed -     
 process out of memory
1: node::Abort() [/usr/local/bin/node]
2: 0x11ef43c [/usr/local/bin/node]
3: v8::Utils::ReportOOMFailure(char const*, bool) [/usr/local/bin/node]
4: v8::internal::V8::FatalProcessOutOfMemory(char const*, bool) 
 [/usr/local/bin/node]
5:v8::internal::Deoptimizer::EnsureCodeForDeoptimizationEntry
(v8::internal::Isolate*, v8::internal::Deoptimizer::BailoutType, int) 
[/usr/local/bin/node]
6: v8::internal::Deoptimizer::EnsureCodeForMaxDeoptimizationEntries
(v8::internal::Isolate*) [/usr/local/bin/node]
7: v8::internal::compiler::PipelineCompilationJob::PrepareJobImpl() 
[/usr/local/bin/node]
8: v8::internal::CompilationJob::PrepareJob() [/usr/local/bin/node]
9: 0xd9a7af [/usr/local/bin/node]
10: v8::internal::Compiler::CompileOptimized
(v8::internal::Handle<v8::internal::JSFunction>, 
v8::internal::ConcurrencyMode) [/usr/local/bin/node]
11: v8::internal::Runtime_CompileOptimized_Concurrent(int, 
v8::internal::Object**, v8::internal::Isolate*) [/usr/local/bin/node]
12: 0x1e20022042fd

错误本身是在processing()期间我的节点处理分叉时导致的，但是，根据memwatch-next的结果，Firebase更新步骤中会出现内存丢失。这是Firebase中的一个现有错误吗？

Firebase更新内存泄漏

0 个答案: