You can force Glide to clear the target via:

Glide.clear(imageView);

but that should happen automatically where Fragments are available. What did you pass to Glide.with when loading the GIF into the ImageView? Feel free to share your full Glide load line.

I pass Activity to Glide.with(), no fragments involved.

Glide.with(this)
.load(file_path)
.diskCacheStrategy(DiskCacheStrategy.NONE)
.skipMemoryCache(true)
.into(imageView);

I tried Glide.clear(imageView) on Activity close, no effect. Still rawData remains allocated.

I thought you're aware about the problem. If you're not I need to ensure I don't miss anything, could just be my fault.

Looks like some GifResourceDecoder.DECODER_POOL references GifDecoder. That's why GifDecoder is retained forever and huge rawData inside it.

Can't see GifResourceDecoder.DECODER_POOL in the latest sources, probably the issue is already fixed? I build against 3.6.1.

I pass Activity to Glide.with(), no fragments involved.

I wanted to know this because it means that Glide can add its own viewless [Support]RequestManagerFragment to the activity which in turn means that the imageView should be cleared upon destroy.

Sadly I'm not familiar with the 4.0 codebase yet, it's possible that the pool was just moved to another class or renamed. Did you customize 3.6.1 or it's just a jar or compile dependency?

Actually, by a quick glance at GifDecoder it simply doesn't clear rawData, it will wait for that buffer to be GC'd only when the decoder is next used. If you check 4.0 GifDecoder changed a lot and that one nulls rawData in clear().

Glide can add its own viewless [Support]RequestManagerFragment to the activity which in turn means that the imageView should be cleared upon destroy.

I see. Probably GifDecoder is not cleared even when ImageView is cleared.

I don't customize anything, I just add "compile 'com.github.bumptech.glide:glide:3.6.1'"

I'll provide issue template, just give me some time.

it will wait for that buffer to be GC'd only when the decoder is next used

Can confirm that. I can see that Gif1 memory is released only when I display another Gif2. If I never display another gif then memory seems to be never released.

If you check 4.0 GifDecoder changed a lot and that one nulls rawData in clear().

Have just tried the latest snapshot build from master. No effect, still the same problem.

I found a really hacky way that may allow for further confirmation and maybe as a temporary workaround. It is untested and may interfere with Glide internals (e.g. when using a normal Glide.with.load.into without any as*() calls).

.asGif()
.decoder(new Issue690GifResourceDecoder(context))

package com.bumptech.glide.load.resource.gif; // need to be in same package to access package private stuff

import android.content.Context;

import com.bumptech.glide.Glide;
import com.bumptech.glide.gifdecoder.*;

public class Issue690GifResourceDecoder extends GifResourceDecoder {
    private static final GifHeaderParserPool PARSER_POOL = new GifHeaderParserPool(); // package private class
    private static final GifDecoderPool DECODER_POOL = new Issue690GifDecoderPool();
    public FixedGifResourceDecoder(Context context) {
        super(context, Glide.get(context).getBitmapPool(), PARSER_POOL, DECODER_POOL); // package private ctor
    }

    static class Issue690GifDecoderPool extends GifDecoderPool { // package private class
        private static final byte[] NO_DATA = new byte[0];
        private static final GifHeader EMPTY_HEADER = new GifHeader();
        @Override public synchronized void release(GifDecoder decoder) {
            decoder.clear(); // clear
            decoder.setData(EMPTY_HEADER, NO_DATA); // set dummy data
            super.release(decoder); // clear again so only dummy data is leaked
        }
    }
}

@thest1 it could be fixed in 3.7.0-SNAPSHOT from build 5 via #892, you can give it a try.

A similar fix to the one in that PR made it into master at some point as well: https://github.com/bumptech/glide/blob/master/third_party/gif_decoder/src/main/java/com/bumptech/glide/gifdecoder/GifDecoder.java#L417

Oh, true that, I said the same above: "If you check 4.0 GifDecoder changed a lot and that one nulls rawData in clear().". I must've confused this issue with something else.