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() PMDK Programmer's Manual ()

NAME

pmempool-transform - Modify internal structure of a pool set.

SYNOPSIS

pmempool transform [options] <poolset_file_src> <poolset_file_dst>
    

NOTE

NOTICE: The libpmemblk and libpmemlog libraries are deprecated since PMDK 1.13.0 release.

DESCRIPTION

The pmempool transform command modifies internal structure of a pool set defined by the poolset_file_src file, according to a structure described in the poolset_file_dst file.

The following operations are supported:

adding replicas - one or more new replicas can be added and synchronized with other replicas in the pool set,
removing replicas - one or more replicas can be removed from the pool set ,
adding or removing pool set options.

Only one of the above operations can be performed at a time.

Currently adding and removing replicas are allowed only for pmemobj pools (see libpmemobj(7)).

The poolset_file_src argument provides the source pool set to be changed.

The poolset_file_dst argument points to the target pool set.

Available options:

Enable dry run mode. In this mode no changes are applied, only check for viability of the operation is performed.
Increase verbosity level.
Display help message and exit.

EXAMPLES

Example 1.

Let files /path/poolset_file_src and /path/poolset_file_dst have the following contents:

PMEMPOOLSET
20M /0/partfile1
20M /0/partfile2
25M /0/partfile3
REPLICA
40M /1/partfile1
20M /1/partfile2
    
PMEMPOOLSET
20M /0/partfile1
20M /0/partfile2
25M /0/partfile3
REPLICA
40M /1/partfile1
20M /1/partfile2
REPLICA
50M /2/partfile1
20M /2/partfile2
    

Then, the command

pmempool transform /path/poolset_file_src /path/poolset_file_dst

adds a replica to the pool set. All other replicas remain unchanged and the size of the pool remains 60M.

Example 2.

Let files /path/poolset_file_src and /path/poolset_file_dst have the following contents:

PMEMPOOLSET
20M /0/partfile1
20M /0/partfile2
25M /0/partfile3
REPLICA
40M /1/partfile1
20M /1/partfile2
    
PMEMPOOLSET
20M /0/partfile1
20M /0/partfile2
25M /0/partfile3
    

Then

pmempool_transform /path/poolset_file_src /path/poolset_file_dst

deletes the second replica from the pool set. The first replica remains unchanged and the size of the pool is still 60M.

SEE ALSO

pmempool(1), libpmemblk(7), libpmemlog(7), libpmempool(7) and <https://pmem.io>

2023-05-31 PMDK -