@Test
public void preallocateGrowShrink() throws Exception {
FileIO fio = FileIO.open(file, EnumSet.of(OpenOption.CREATE, OpenOption.PREALLOCATE));
for (long len = 0; len <= 50_000L; len += 5000L) {
fio.setLength(len);
assertEquals(len, fio.length());
}
for (long len = 50_000L; len >= 0; len -= 5000L) {
fio.setLength(len);
assertEquals(len, fio.length());
}
fio.close();
}
@Ignore
@Test
public void crash() throws Exception {
// Reproduces SIGBUS crash. Requires writing direct buffers
// to a mapped file when there is not enough space left. To avoid having
// to fill up a primary device use a small ramdisk, or loop device. E.g.
// $ dd if=/dev/zero of=file.img bs=1M count=100
// $ losetup /dev/loop0 file.img
// $ mkfs.ext4 /dev/loop0
// $ mkdir -p root
// $ mount -t ext4 /dev/loop0 root
assumeTrue(Platform.isLinux());
File f = new File("root/test.file");
if (f.exists()) f.delete();
FileIO fio = FileIO.open(f, EnumSet.of(OpenOption.CREATE, OpenOption.PREALLOCATE));
final long len = f.getTotalSpace() * 5L;
fio.setLength(len);
fio.map();
ByteBuffer bb = ByteBuffer.allocateDirect(4097);
for (long pos = 0; pos < len - bb.remaining(); pos += 512) {
fio.write(pos, bb);
bb.flip();
}
fio.close();
}
@Test
public void preallocateTooLarge() throws Exception {
assumeTrue(Platform.isLinux());
FileIO fio =
FileIO.open(file, EnumSet.of(OpenOption.CREATE, OpenOption.MAPPED, OpenOption.PREALLOCATE));
FileStore fs = Files.getFileStore(file.toPath());
assumeTrue("ext4".equals(fs.type()) && !fs.name().contains("docker"));
long len = file.getTotalSpace() * 100L;
// setLength traps the IOException and prevents resizing / remapping. Not remapping avoids
// the SIGBUS issue.
fio.setLength(len);
assertEquals(0, fio.length());
fio.close();
}
@Test
public void preallocate() throws Exception {
// Assuming a filesystem with delayed block allocation,
// e.g. ext3 / ext4 on Linux.
assumeTrue(Platform.isLinux() || Platform.isMac());
long len = 100L * (1 << 20); // 100 MB
FileIO fio = FileIO.open(file, EnumSet.of(OpenOption.CREATE, OpenOption.PREALLOCATE));
long startFree = file.getFreeSpace();
fio.setLength(len);
long alloc = startFree - file.getFreeSpace();
// Free space should be reduced. Pad expectation since external
// events may interfere.
assertTrue(alloc > (len >> 1));
fio.close();
}