Abstract: Delay commands are injected into sequential input/output (I/O) requests and the effects of the injected delay commands are measured for determining whether a storage system handling the sequential input/output (IO) requests is causing a bottleneck.

Abstract: For efficiently storing and retrieving data and metadata in phases, in a first phase, metadata tokens, which are assigned to most active metadata-emitting entities, are used for storing the data and the metadata together in a single input/output operation while piggybacking the metadata of least active metadata-emitting entities onto one of the most active metadata-emitting entities having one of the metadata tokens. In a second phase, the metadata is re-written to a metadata delta journal for reclaiming the metadata tokens. In a third phase, the metadata journal is applied to a metadata structure containing the metadata of the storage system, the metadata delta journal is then cleared after successfully updating the main metadata structure with the metadata of the metadata journal. The metadata journal is swapped with an empty metadata journal for concurrently adding metadata while retaining the metadata journal until applying the metadata delta journal to the metadata structure.

Abstract: Various embodiments for transforming a logical data object for storage in a storage device operable with at least one storage protocol are provided. In one such embodiment, the logical data object into one or more segments are divided with each segment characterized by respective start and end offsets. One or more obtained variable size data chunks are processed corresponding to the logical data object to obtain processed data chunks, wherein at least one of the processed data chunks comprises transformed data resulting from the processing. Each of the variable size data chunks is associated with a respective segment of the logical data object. The processed data chunks are sequentially accommodated in accordance with an order of chunks received while keeping the association with the respective segments.

Abstract: Various embodiments for transforming a logical data object for storage in a storage device operable with at least one storage protocol are provided. In one such embodiment, the logical data object into one or more segments are divided with each segment characterized by respective start and end offsets. One or more obtained variable size data chunks are processed corresponding to the logical data object to obtain processed data chunks, wherein at least one of the processed data chunks comprises transformed data resulting from the processing. Each of the variable size data chunks is associated with a respective segment of the logical data object. The processed data chunks are sequentially accommodated in accordance with an order of chunks received while keeping the association with the respective segments.

Abstract: Exemplary system and computer program product embodiments compression blocks input/output (I/O) reduction are provided. In one embodiment, by way of example only, data blocks are arranged into groups to provide a single I/O. Lists indicating the available block space for the data blocks are organized in advance according to space size. The data blocks required for a single command are allocated as the single I/O. The data blocks are sequentially ordered. Additional system and computer program product embodiments are disclosed and provide related advantages.

Abstract: Exemplary method, system, and computer program product embodiments compression blocks input/output (I/O) reduction are provided. In one embodiment, by way of example only, data blocks are arranged into groups to provide a single I/O. Lists indicating the available block space for the data blocks are organized in advance according to space size. The data blocks required for a single command are allocated as the single I/O. The data blocks are sequentially ordered. Additional system and computer program product embodiments are disclosed and provide related advantages.

Abstract: For on-line separation of data chunks for compression, unrelated data chunks are classified based on various attributes. The classified data chunks are sent to at least one available compression contexts. The classified data chunks are related. The classified data chunks are encoded by at least one the compression operations. A compression ratio is achieved and included as feedback.

Abstract: A data chunk is compressed into a storage block when emitting the data chunk. If the data chunk is unable to be completely compressed into the storage block, attributes of the data chunk are analyzed for determining whether the data chunk should be split. If the data chunk should be split, a remaining portion of the data chunk is compressed to a next chronological storage block. If the data chunk should not be split, all of the data chunk is moved to the next chronological storage block while leaving any remaining space in the storage block as unused.

Abstract: A data chunk is compressed into a storage block when emitting the data chunk. If the data chunk is unable to be completely compressed into the storage block, attributes of the data chunk are analyzed for determining whether the data chunk should be split. If the data chunk should be split, a remaining portion of the data chunk is compressed to a next chronological storage block. If the data chunk should not be split, all of the data chunk is moved to the next chronological storage block while leaving any remaining space in the storage block as unused.

Abstract: Exemplary method, system, and computer program product embodiments for real-time image recompression are provided. In one embodiment, by way of example only, compressed segments that are identified as having used at least one of a plurality of inefficient compression operations are partially decoded. The compressed segments are recompressed by employing context mapping. Additional system and computer program product embodiments are disclosed and provide related advantages.

Abstract: For efficiently storing and retrieving data and metadata in phases, in a first phase, metadata tokens, which are assigned to most active metadata-emitting entities, are used for storing the data and the metadata together in a single input/output operation while piggybacking the metadata of least active metadata-emitting entities onto one of the most active metadata-emitting entities having one of the metadata tokens. In a second phase, the metadata is re-written to a metadata delta journal for reclaiming the metadata tokens. In a third phase, the metadata journal is applied to a metadata structure containing the metadata of the storage system, the metadata delta journal is then cleared after successfully updating the main metadata structure with the metadata of the metadata journal. The metadata journal is swapped with an empty metadata journal for concurrently adding metadata while retaining the metadata journal until applying the metadata delta journal to the metadata structure.

Abstract: For efficiently storing and retrieving data and metadata in phases, in a first phase, metadata tokens, which are assigned to most active metadata-emitting entities, are used for storing the data and the metadata together in a single input/output operation while piggybacking the metadata of least active metadata-emitting entities onto one of the most active metadata-emitting entities having one of the metadata tokens. In a second phase, the metadata is re-written to a metadata delta journal for reclaiming the metadata tokens. In a third phase, the metadata journal is applied to a metadata structure containing the metadata of the storage system, the metadata delta journal is then cleared after successfully updating the main metadata structure with the metadata of the metadata journal. The metadata journal is swapped with an empty metadata journal for concurrently adding metadata while retaining the metadata journal until applying the metadata delta journal to the metadata structure.

Abstract: A compression system configured to compress logical data objects into one or more accommodation blocks with a predefined size, and a method of operating thereof are provided. The compression system includes a compression engine capable of compressing input data with the help of sequential encoding one or more input strings and a counter operatively coupled to the compression engine. The counter is configured to keep its ongoing value indicative of a number of input bytes in one or more strings successfully encoded into a given accommodation block; and, responsive to unsuccessful compression of a string into the given accommodation block, to provide the compression engine with information indicative of starting point in the input stream for encoding into the next accommodation block, thus giving rise to a “start indication.

Abstract: A compression system configured to compress logical data objects into one or more accommodation blocks with a predefined size, and a method of operating thereof are provided. The compression system includes a compression engine capable of compressing input data with the help of sequential encoding one or more input strings and a counter operatively coupled to the compression engine. The counter is configured to keep its ongoing value indicative of a number of input bytes in one or more strings successfully encoded into a given accommodation block; and, responsive to unsuccessful compression of a string into the given accommodation block, to provide the compression engine with information indicative of starting point in the input stream for encoding into the next accommodation block, thus giving rise to a “start indication.

Abstract: Exemplary methods, computer systems, and computer program products for processing a previously compressed data stream in a computer environment are provided. In one embodiment, the computer environment is configured for separating a previously compressed data stream into an input data block including a header input block having a previously compressed header. Sequences of bits are included with the input data block. Compression scheme information is derived from the previously compressed header. The input data block is accessed and recompressed following the header input block in the previously compressed data stream one at a time using block-image synchronization information. Access to the block-image synchronization information is initialized by the compression scheme information to generate an output data block. The block-image synchronization information is used to provide decompression information to facilitate decompression of the results of the output data block.

Abstract: Exemplary methods, computer systems, and computer program products for processing a previously compressed data stream in a computer environment are provided. In one embodiment, the computer environment is configured for separating a previously compressed data stream into an input data block including a header input block having a previously compressed header. Sequences of bits are included with the input data block. Compression scheme information is derived from the previously compressed header. The input data block is accessed and recompressed following the header input block in the previously compressed data stream one at a time using block-image synchronization information. Access to the block-image synchronization information is initialized by the compression scheme information to generate an output data block. The block-image synchronization information is used to provide decompression information to facilitate decompression of the results of the output data block.

Abstract: Exemplary method, system, and computer program product embodiments for real-time column compression of data are provided. In one embodiment, by way of example only, a data structure is estimated for an initially unknown structured data. The estimated data structure is placed in a stream. A columnar compression operation is applied to the stream to generate an achieved compression ratio. The stream is compressed. Feedback of the achieved compression ratio is analyzed from the stream to determine if an optimal one of the columnar compression operations has been applied. If the optimal one of the columnar compression operations has been applied, the actual data structure of the initially unknown structured data is determined.

Abstract: Exemplary system and computer program product embodiments compression blocks input/output (I/O) reduction are provided. In one embodiment, by way of example only, data blocks are arranged into groups to provide a single I/O. Lists indicating the available block space for the data blocks are organized in advance according to space size. The data blocks required for a single command are allocated as the single I/O. The data blocks are sequentially ordered. Additional system and computer program product embodiments are disclosed and provide related advantages.

Abstract: For on-line separation of data chunks for compression, unrelated data chunks are classified based on various attributes. The classified data chunks are sent to at least one available compression contexts. The classified data chunks are related. The classified data chunks are encoded by at least one the compression operations. A compression ratio is achieved and included as feedback.

Abstract: For on-line separation of data chunks for compression, unrelated data chunks are classified based on various attributes. The classified data chunks are sent to at least one available compression contexts. The classified data chunks are related. The classified data chunks are encoded by at least one the compression operations. A compression ratio is achieved and included as feedback.