filerep_*

The filerep* tables store high-availability file replication process information for a Greenplum Database instance. There are three filerep tables, all having the same columns:

filerep_now is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. Current file replication data is stored in filerep_now during the period between data collection from the Command Center agents and automatic commitment to the filerep_history table.
filerep_tail is an external table whose data files are stored in $MASTER_DATA_DIRECTORY/gpperfmon/data. This is a transitional table for file replication data that has been cleared from filerep_now but has not yet been committed to filerep_history. It typically only contains a few minutes worth of data.
filerep_history is a regular table that stores historical database-wide file replication data. It is pre-partitioned into monthly partitions. Partitions are automatically added in two month increments as needed. Administrators must drop old partitions for the months that are no longer needed.

Column	Type	Description
`ctime`	timestamp	Time this row was created.
`primary_measurement_microsec`	bigint	The length of time over which primary metrics (contained in UDP messages) were gathered.
`mirror_measurement_microsec`	bigint	The length of time over which mirror metrics (contained in UDP messages) were gathered.
`primary_hostname`	varchar(64)	The name of the primary host.
`primary_port`	int	The port number of the primary host.
`mirror_hostname`	varchar(64)	The name of the mirror host.
`mirror_port`	int	The port number of the mirror host.
`primary_write_syscall_bytes_avg`	bigint	The average amount of data written to disk on the primary for write system calls per interval.
`primary_write_syscall_byte_max`	bigint	The maximum amount of data written to disk on the primary for write system calls per interval.
`primary_write_syscall_microsecs_avg`	bigint	The average time required for a write system call to write data to disk on the primary per interval.
`primary_write_syscall_microsecs_max`	bigint	The maximum time required for a write system call to write data to disk on the primary per interval.
`primary_write_syscall_per_sec`	double precision	The number of write system calls on the primary per second. It reflects only the time to queue the write to disk in memory.
`primary_fsync_syscall_microsec_avg`	bigint	The average amount of time required for a file sync system call to write data to disk on the primary per interval.
`primary_fsync_syscall_microsec_max`	bigint	The maximum amount of time required for a file sync system call to write data to disk on the primary per interval.
`primary_fsync_syscall_per_sec`	double precision	The number of file sync system calls on the primary per second. Unlike write system calls which return immediately after the data is posted/queued, file sync system calls wait for all outstanding writes to be written to disk. File sync system call values in this column reflect actual disk access times for potentially large amounts of data.
`primary_write_shmem_bytes_avg`	bigint	The average amount of data written to shared memory on the primary per interval.
`primary_write_shmem_bytes_max`	bigint	The maximum amount of data written to shared memory on the primary per interval.
`primary_write_shmem_microsec_avg`	bigint	The average amount of time required to write data to shared memory on the primary per interval.
`primary_write_shmem_microsec_max`	bigint	The maximum amount of time required to write data to shared memory on the primary per interval.
`primary_write_shmem_per_sec`	double precision	The number of writes to shared memory on the primary per second.
`primary_fsync_shmem_microsec_avg`	bigint	The average amount of time required by the file sync system call to write data to shared memory on the primary per interval.
`primary_fsync_shmem_microsec_max`	bigint	The maximum amount of time required by the file sync system call to write data to shared memory on the primary per interval.
`primary_fsync_shmem_per_sec`	double precision	The number of file sync calls to shared memory on the primary per second. File sync system call values in this column reflect actual disk access times for potentially large amounts of data.
`primary_write_shmem_per_sec`	double precision	The number of writes to shared memory on the primary per second.
`primary_fsync_shmem_microsec_avg`	bigint	The average amount of time required by the file sync system call to write data to shared memory on the primary per interval.
`primary_fsync_shmem_microsec_max`	bigint	The maximum amount of time required by the file sync system call to write data to shared memory on the primary per interval.
`primary_fsync_shmem_per_sec`	double precision	The number of file sync calls to shared memory on the primary per second. File sync system call values in this column reflect actual disk access times for potentially large amounts of data.
`primary_roundtrip_fsync_msg_microsec_avg`	bigint	The average amount of time required for a roundtrip file sync between the primary and the mirror per interval. This includes: The queuing of a file sync message from the primary to the mirror. The message traversing the network. The execution of the file sync by the mirror. The file sync acknowledgement traversing the network back to the primary.
`primary_roundtrip_fsync_msg_microsec_max`	bigint	The maximum amount of time required for a roundtrip file sync between the primary and the mirror per interval. This includes: The queuing of a file sync message from the primary to the mirror. The message traversing the network. The execution of the file sync by the mirror. The file sync acknowledgement traversing the network back to the primary.
`primary_roundtrip_fsync_msg_per_sec`	double precision	The number of roundtrip file syncs per second.
`primary_roundtrip_test_msg_microsec_avg`	bigint	The average amount of time required for a roundtrip test message between the primary and the mirror to complete per interval. This is similar to `primary_roundtrip_fsync_msg_microsec_avg`, except it does not include a disk access component. Because of this, this is a useful metric that shows the average amount of network delay in the file replication process.
`primary_roundtrip_test_msg_microsec_max`	bigint	The maximum amount of time required for a roundtrip test message between the primary and the mirror to complete per interval. This is similar to `primary_roundtrip_fsync_msg_microsec_max`, except it does not include a disk access component. Because of this, this is a useful metric that shows the maximum amount of network delay in the file replication process.
`primary_roundtrip_test_msg_per_sec`	double precision	The number of roundtrip file syncs per second. This is similar to `primary_roundtrip_fsync_msg_per_sec`, except it does not include a disk access component. As such, this is a useful metric that shows the amount of network delay in the file replication process. Note that test messages typically occur once per minute, so it is common to see a value of “0” for time periods not containing a test message.
`mirror_write_syscall_size_avg`	bigint	The average amount of data written to disk on the mirror for write system calls per interval.
`mirror_write_syscall_size_max`	bigint	The maximum amount of data written to disk on the mirror for write system calls per interval.
`mirror_write_syscall_microsec_avg`	bigint	The average time required for a write system call to write data to disk on the mirror per interval.
`mirror_write_syscall_microsec_max`	bigint	The maximum time required for a write system call to write data to disk on the mirror per interval.
`primary_roundtrip_test_msg_per_sec`	double precision	The number of roundtrip file syncs per second. This is similar to `primary_roundtrip_fsync_msg_per_sec`, except it does not include a disk access component. As such, this is a useful metric that shows the amount of network delay in the file replication process. Note that test messages typically occur once per minute, so it is common to see a value of “0” for time periods not containing a test message.
`mirror_write_syscall_size_avg`	bigint	The average amount of data written to disk on the mirror for write system calls per interval.
`mirror_write_syscall_size_max`	bigint	The maximum amount of data written to disk on the mirror for write system calls per interval.
`mirror_write_syscall_microsec_avg`	bigint	The average time required for a write system call to write data to disk on the mirror per interval.