Android/frameworks_base
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

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

Browse Source 
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
This commit is contained in:
Yi-Yo Chiang
2022-03-20 16:49:32 +08:00
parent 6287488399
commit 9b4f3eaf17
1 changed files with 8 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
packages/DynamicSystemInstallationService/src/com/android/dynsystem/SparseInputStream.java
View File

@@ -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();