Thread: pgsql: Improve comment on top of pgstat_count_io_op_time()

Improve comment on top of pgstat_count_io_op_time()

This commit adds more documentation to pgstat_count_io_op_time() in
pgstat_io.c, explaining its internals for pgstat_count_buffer_*(),
pgBufferUsage and the contexts where these are used.

Extracted from a larger patch by the same author.

Author: Nazir Bilal Yavuz
Discussion: https://postgr.es/m/CAN55FZ3AiQ+ZMxUuXnBpd0Rrh1YhwJ5FudkHg=JU0P+-W8T4Vg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b998fedab74c6cf4e564c17f4171881759a093ee

Modified Files
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src/backend/utils/activity/pgstat_io.c | 8 ++++++++
1 file changed, 8 insertions(+)