alluxio.master.file.meta

Interface UfsBlockLocationCache

All Known Implementing Classes:

LazyUfsBlockLocationCache

public interface UfsBlockLocationCache

Cache for block locations in the UFS.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	UfsBlockLocationCache.Factory Factory class for UfsBlockLocationCache.

Method Summary

Modifier and Type	Method and Description
List<String>	get(long blockId)
List<String>	get(long blockId, AlluxioURI fileUri, long offset) If the locations exist in the cache, return them, otherwise, retrieves the block locations from UFS, and caches the result.
void	invalidate(long blockId) Invalidates the UFS locations for the block.

Method Detail

get

List<String> get(long blockId)

Parameters:

blockId - the block ID

Returns:

the cached block locations or null if there is no cached locations for the block

get

List<String> get(long blockId,
                 AlluxioURI fileUri,
                 long offset)

If the locations exist in the cache, return them, otherwise, retrieves the block locations from UFS, and caches the result. If failed to get the locations from UFS, null is returned and nothing is cached.

Parameters:

blockId - the block ID

fileUri - the URI of the file which contains the block

offset - the block's offset in the file

Returns:

the block locations or null if it fails to get the locations from UFS

invalidate

void invalidate(long blockId)

Invalidates the UFS locations for the block.

Parameters:

blockId - the block ID