Remote copy system and remote copy method
A primary storage system reads a plurality of journal data, and performs collective compression that is compression of data that is at least a part of the plurality of pieces of journal data in the plurality of journals and is larger than a size of one journal data. The collectively compressed data, which is a plurality of pieces of journal data subjected to collective compression, is a transfer target from the primary storage system to the secondary storage system. The journal is journal data and metadata including a write order of the journal data and associated with the journal data. The journal data is a copy of data written in the primary volume. The secondary storage system acquires a plurality of pieces of journal data by decompressing one or more pieces of collectively compressed data, and writes the plurality of pieces of journal data to the secondary volume.
1. A computer system comprising:
a primary storage system having a primary volume; and
a secondary storage system including a secondary volume configuring a volume pair with the primary volume,
wherein:
the primary storage system performs collective compression that is collective compression of data of a plurality of journals,
the collectively compressed data and metadata, corresponding to the collectively compressed data, are transfer targets from the primary storage system to the secondary storage system,
each of the plurality of journals is configured from journal data and journal metadata which is associated with the journal data,
the journal data is a copy of data stored in the primary volume, and
the secondary storage system acquires a plurality of pieces of journal data by decompressing one or more pieces of the collectively compressed data, and writes the plurality of pieces of journal data to the secondary volume.
2. The computer system according to claim 1 , wherein
the secondary storage system writes the plurality of pieces of journal data to the secondary volume according to a write order represented by the metadata.
3. The computer system according to claim 1 , wherein
both the primary storage system and the secondary storage system or one of them is a system on a cloud.
4. The computer system according to claim 1 , wherein
at least one of the primary storage system and the secondary storage system has a network interface which performs transfer between the primary storage system and the secondary storage system, and
the network interface performs at least either the collective compression or the decompression.
5. The computer system according to claim 1 , wherein, for each journal I/O request, the collectively compressed data and the metadata are transferred from the primary storage system to the secondary storage system, the metadata are N (N is an integer of 1 or more) pieces of the journal metadata in N journals of the plurality of journals, and
the journal I/O request is either a journal read request from the secondary storage system to the primary storage system or a journal write request from the primary storage system to the secondary storage system.
6. The computer system according to claim 5 , wherein, the data of the plurality of journals is N pieces of the journal data, and, for each of the journal I/O request, the primary storage system reads the N pieces of the journal data and collectively compresses the N pieces of the journal data.
7. The computer system according to claim 1 , wherein
the primary storage system specifies a plurality of journals that have not been transferred to the secondary storage system each time one or more journals, of the plurality of journals, are transferred to the secondary storage system, and performs the collective compression on the plurality of specified journals,
the metadata in the transfer targets includes information indicating that compression is performed and information indicating a compressed size that is a size of the collectively compressed data, for each transfer for which the collective compression is performed, and
for each transfer for which the collective compression is performed, in a case where the metadata includes information indicating that compression is performed, the secondary storage system decompresses the collectively compressed data of the compressed size indicated by the metadata.
8. The computer system according to claim 1 , wherein
a reception size that is an upper limit of a data size that can be received by a compression function of the primary storage system is determined,
the primary storage system divides plurality of pieces of the journal data by a division size equal to or smaller than the reception size,
the compression function outputs a plurality of compressed data segments by compressing each of a plurality of data segments obtained by dividing the plurality of pieces of the journal data by the division size, and
the collectively compressed data is data configured by the plurality of compressed data segments.
9. The computer system according to claim 8 , wherein
the secondary storage system acquires the plurality of compressed data segments by dividing the collectively compressed data by a compressed size specified from each metadata of respective compressed data segment of the plurality of compressed data segments, and decompresses each of the plurality of compressed data segments.
10. The computer system according to claim 9 , wherein
the compression function is an accelerator of compression.
11. The computer system according to claim 10 , wherein
in a case where the secondary volume is associated with the primary volume as a pairing partner, formed copy is performed in which a content of the secondary volume matches a content of the primary volume, and
in the formed copy, the accelerator compresses each data segment each time data is transferred from the primary storage system to the secondary storage system.
12. The computer system according to claim 1 , wherein for each wire request designating the primary volume, the primary storage system performs write processing including writing respective data accompanying the write request to the primary volume, storing respective journal data which is a copy of the respective data and storing respective metadata including a write order of the respective journal data, and
the primary storage system performs a completion response of the write request for each of the write request designating the primary volume without waiting for storage and collective compression of respective journal data of respective data accompanying the write request.
13. The computer system according to claim 1 , wherein
the secondary storage system transmits a journal read request to the primary storage system,
the transfer targets are transferred from the primary storage system to the secondary storage system in response to the journal read request,
the metadata in the transfer targets include information indicating that compression is performed, and
if the transfer targets comprise the collective compressed data, the secondary storage system decompresses the collectively compressed data, and writes the decompressed collectively compressed data to the secondary volume.
14. A computer system control method performed by a primary storage system having a primary volume and a secondary storage system including a secondary volume configuring a volume pair with the primary volume, the method comprising:
performing, by the primary storage system, collective compression that is collective compression of data of a plurality of journals, wherein
the collectively compressed data and a plurality of pieces of metadata, corresponding to the collectively compressed data, are transfer targets from the primary storage system to the secondary storage system,
each of the plurality of journals is configured from journal data and journal metadata which is associated with the journal data, and
the journal data is a copy of data written in the primary volume; and
acquiring, by the secondary storage system, a plurality of pieces of journal data by decompressing one or more pieces of the collectively compressed data, and writing the plurality of pieces of journal data to the secondary volume.