SUMMARY_FILE_IOSTAT

Records statistics about data file I/Os in the database to indicate I/O performance and detect performance problems such as abnormal I/O operations, as shown in Table 1.

The values of phyrds, phywrts, phyblkrd, phyblkwrt, readtim and writetim are summed up based on the data of each node. avgiotim is the average value (total duration/total times) of each node. lstiotim and maxiowtm are the maximum values of each node. miniotim is the minimum value of each node.

**Table 1** SUMMARY_FILE_IOSTAT columns
Name	Type	Description
filenum	oid	File ID
dbid	oid	Database ID
spcid	oid	Tablespace ID
phyrds	numeric	Number of times of reading physical files
phywrts	numeric	Number of times of writing into physical files
phyblkrd	numeric	Number of times of reading physical file blocks
phyblkwrt	numeric	Number of times of writing into physical file blocks
readtim	numeric	Total duration of reading (unit: μs)
writetim	numeric	Total duration of writing (unit: μs)
avgiotim	bigint	Average duration of reading and writing (unit: μs)
lstiotim	bigint	Duration of the last file reading (unit: μs)
miniotim	bigint	Minimum duration of reading and writing (unit: μs)
maxiowtm	bigint	Maximum duration of reading and writing (unit: μs)