/** @throws Exception If failed. */
public void testCreateFileColocated() throws Exception {
GridGgfsPath path = new GridGgfsPath("/colocated");
UUID uuid = UUID.randomUUID();
GridUuid affKey;
long idx = 0;
while (true) {
affKey = new GridUuid(uuid, idx);
if (grid(0).mapKeyToNode(DATA_CACHE_NAME, affKey).id().equals(grid(0).localNode().id()))
break;
idx++;
}
try (GridGgfsOutputStream out = fs.create(path, 1024, true, affKey, 0, 1024, null)) {
// Write 5M, should be enough to test distribution.
for (int i = 0; i < 15; i++) out.write(new byte[1024 * 1024]);
}
GridGgfsFile info = fs.info(path);
Collection<GridGgfsBlockLocation> affNodes = fs.affinity(path, 0, info.length());
assertEquals(1, affNodes.size());
Collection<UUID> nodeIds = F.first(affNodes).nodeIds();
assertEquals(1, nodeIds.size());
assertEquals(grid(0).localNode().id(), F.first(nodeIds));
}
/**
* Eviction policy based on {@code First In First Out (FIFO)} algorithm. This implementation is very
* efficient since it does not create any additional table-like data structures. The {@code FIFO}
* ordering information is maintained by attaching ordering metadata to cache entries.
*/
public class GridCacheFifoEvictionPolicy<K, V>
implements GridCacheEvictionPolicy<K, V>, GridCacheFifoEvictionPolicyMBean {
/** Tag. */
private final String meta = UUID.randomUUID().toString();
/** Maximum size. */
private volatile int max = GridCacheConfiguration.DFLT_CACHE_SIZE;
/** FIFO queue. */
private final ConcurrentLinkedDeque8<GridCacheEntry<K, V>> queue = new ConcurrentLinkedDeque8<>();
/** Constructs FIFO eviction policy with all defaults. */
public GridCacheFifoEvictionPolicy() {
// No-op.
}
/**
* Constructs FIFO eviction policy with maximum size. Empty entries are allowed.
*
* @param max Maximum allowed size of cache before entry will start getting evicted.
*/
public GridCacheFifoEvictionPolicy(int max) {
A.ensure(max > 0, "max > 0");
this.max = max;
}
/**
* Gets maximum allowed size of cache before entry will start getting evicted.
*
* @return Maximum allowed size of cache before entry will start getting evicted.
*/
@Override
public int getMaxSize() {
return max;
}
/**
* Sets maximum allowed size of cache before entry will start getting evicted.
*
* @param max Maximum allowed size of cache before entry will start getting evicted.
*/
@Override
public void setMaxSize(int max) {
A.ensure(max > 0, "max > 0");
this.max = max;
}
/** {@inheritDoc} */
@Override
public int getCurrentSize() {
return queue.size();
}
/** {@inheritDoc} */
@Override
public String getMetaAttributeName() {
return meta;
}
/**
* Gets read-only view on internal {@code FIFO} queue in proper order.
*
* @return Read-only view ono internal {@code 'FIFO'} queue.
*/
public Collection<GridCacheEntry<K, V>> queue() {
return Collections.unmodifiableCollection(queue);
}
/** {@inheritDoc} */
@Override
public void onEntryAccessed(boolean rmv, GridCacheEntry<K, V> entry) {
if (!rmv) {
if (!entry.isCached()) return;
// Shrink only if queue was changed.
if (touch(entry)) shrink();
} else {
Node<GridCacheEntry<K, V>> node = entry.removeMeta(meta);
if (node != null) queue.unlinkx(node);
}
}
/**
* @param entry Entry to touch.
* @return {@code True} if queue has been changed by this call.
*/
private boolean touch(GridCacheEntry<K, V> entry) {
Node<GridCacheEntry<K, V>> node = entry.meta(meta);
// Entry has not been enqueued yet.
if (node == null) {
while (true) {
node = queue.offerLastx(entry);
if (entry.putMetaIfAbsent(meta, node) != null) {
// Was concurrently added, need to clear it from queue.
queue.unlinkx(node);
// Queue has not been changed.
return false;
} else if (node.item() != null) {
if (!entry.isCached()) {
// Was concurrently evicted, need to clear it from queue.
queue.unlinkx(node);
return false;
}
return true;
}
// If node was unlinked by concurrent shrink() call, we must repeat the whole cycle.
else if (!entry.removeMeta(meta, node)) return false;
}
}
// Entry is already in queue.
return false;
}
/** Shrinks FIFO queue to maximum allowed size. */
private void shrink() {
int max = this.max;
int startSize = queue.sizex();
for (int i = 0; i < startSize && queue.sizex() > max; i++) {
GridCacheEntry<K, V> entry = queue.poll();
if (entry == null) break;
if (!entry.evict()) {
entry.removeMeta(meta);
touch(entry);
}
}
}
/**
* Checks entry for empty value.
*
* @param entry Entry to check.
* @return {@code True} if entry is empty.
*/
private boolean empty(GridCacheEntry<K, V> entry) {
try {
return entry.peek(F.asList(GLOBAL)) == null;
} catch (GridException e) {
U.error(null, e.getMessage(), e);
assert false : "Should never happen: " + e;
return false;
}
}
/** {@inheritDoc} */
@Override
public String toString() {
return S.toString(GridCacheFifoEvictionPolicy.class, this);
}
}
