Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9b4f3eaf authored by Yi-Yo Chiang's avatar Yi-Yo Chiang
Browse files

dynsystem.SparseInputStream: Implement read(buf, off, len) 

InstallationAsyncTask calls SparseInputStream.read(buf, off, len),
however SparseInputStream didn't override that method, so the method
actually fallbacks to the default implementation, which is a for-loop
calling read() (single byte). This is a significant performance hit.

This modest fix boosts the DSU installation time significantly:
* physical device: 45s -> 15s
* virtual device: 30s -> 7s

Bug: 225310919
Test: start a Dynamic System installation
Change-Id: I5a61dc2e9554719aece43491b813f6647b4bcc65
parent 62874883

packages/DynamicSystemInstallationService/src/com/android/dynsystem/SparseInputStream.java

+8 −12
Original line number Diff line number Diff line
@@ -133,36 +133,32 @@ public class SparseInputStream extends InputStream { 
        return mLeft == 0;

    }



    /**

     * It overrides the InputStream.read(byte[] buf)

     */

    public int read(byte[] buf) throws IOException {

    @Override

    public int read(byte[] buf, int off, int len) throws IOException {

        if (!mIsSparse) {

            return mIn.read(buf);

            return mIn.read(buf, off, len);

        }

        if (prepareChunk()) return -1;

        int n = -1;

        switch (mCur.mChunkType) {

            case SparseChunk.RAW:

                n = mIn.read(buf, 0, (int) min(mLeft, buf.length));

                n = mIn.read(buf, off, (int) min(mLeft, len));

                mLeft -= n;

                return n;

            case SparseChunk.DONTCARE:

                n = (int) min(mLeft, buf.length);

                Arrays.fill(buf, 0, n - 1, (byte) 0);

                n = (int) min(mLeft, len);

                Arrays.fill(buf, off, off + n, (byte) 0);

                mLeft -= n;

                return n;

            case SparseChunk.FILL:

                // The FILL type is rarely used, so use a simple implmentation.

                return super.read(buf);

                return super.read(buf, off, len);

            default:

                throw new IOException("Unsupported Chunk:" + mCur.toString());

        }

    }



    /**

     * It overrides the InputStream.read()

     */

    @Override

    public int read() throws IOException {

        if (!mIsSparse) {

            return mIn.read();