asynchronous drawImage speeds up execution but causes serious memory leaks.

[rambo-panda]

// this is pmap status
0000000000400000    7644    3104       0 r---- node
0000000000b77000       8       8       0 r-x-- node
0000000000b7a000   27296   13892       0 r-x-- node
0000000002800000       4       0       0 r-x-- node
0000000002801000   46796    8980       0 r---- node
00000000055b4000      16      16       8 r---- node
00000000055b8000     124     108      92 rw--- node
00000000055d7000     180     168     168 rw---   [ anon ]
00000000075e0000 5697364 5697132 5697132 rw---   [ anon ]
00000266d94c0000     256     256     256 rw---   [ anon ]
0000033e93480000     256       8       8 rw---   [ anon ]
0000036b35cc0000     256     256     256 rw---   [ anon ]
0000039136800000     256     256     256 rw---   [ anon ]
000003f309900000     256     256     256 rw---   [ anon ]
000004103ff00000     256     256     256 rw---   [ anon ]

The memory does not automatically drop to normal levels, even though I have enabled GC and cleared all cache.

[rambo-panda]

#867

[Horziox]

After several tests on my side and after proceeding by elimination, I confirm I have the same issue.
The buffers generated by drawImage cannot be cleared by Node's Garbage Collector, inevitably leading to a memory leak.

[bingtsingw]

I have the same issue

[rambo-panda]

canvas/src/image.rs

Lines 417 to 424 in 8ca3a9e

	let this: This = env.get_reference_value(&self.this_ref)?;
	let mut image_ptr = ptr::null_mut();
	check_status!(
	unsafe { sys::napi_unwrap(env.raw(), this.raw(), &mut image_ptr) },
	"Failed to unwrap Image from this"
	)?;
	let self_mut = unsafe { Box::leak(Box::from_raw(image_ptr.cast::<Image>())) };
	self_mut.width = output.width;

// 'static pointer
let self_mut = unsafe { Box::leak(Box::from_raw(image_ptr.cast::<Image>())) }; 

[rambo-panda]

canvas/src/image.rs

Lines 417 to 424 in 8ca3a9e

	let this: This = env.get_reference_value(&self.this_ref)?;
	let mut image_ptr = ptr::null_mut();
	check_status!(
	unsafe { sys::napi_unwrap(env.raw(), this.raw(), &mut image_ptr) },
	"Failed to unwrap Image from this"
	)?;
	let self_mut = unsafe { Box::leak(Box::from_raw(image_ptr.cast::<Image>())) };
	self_mut.width = output.width;

// 'static pointer
let self_mut = unsafe { Box::leak(Box::from_raw(image_ptr.cast::<Image>())) }; 

@Brooooooklyn since I have limited understanding of @napi-rs, I am hesitant to change the lifecycle of self_mut rashly. Is it possible to make the following modification for the time being?

  #[napi(setter)]
  pub fn set_src(&mut self, env: Env, this: This, data: Uint8Array) -> Result<()> {
    let length = data.len();
    if length <= 2 {
      self.src = Some(data);
+     self.bitmap = None;
+     self.width = -1.0;
+      self.height = -1.0;

---

Of course, I have my own motives, as it just happens to meet another need of mine. #868

[bingtsingw]

@Brooooooklyn Hi, are there any progress on this issue, it's a serious problem on server, after a few requests, the server memory usage is full.