Queries related to checkpoints

Hi,

I am a Noob with db tuning and trying to analyze pg_stats_brwriter data

checkpoints_timed | checkpoints_req | buffers_checkpoint | buffers_clean |
maxwritten_clean | buffers_backend | buffers_alloc

-------------------+-----------------+--------------------+---------------+------------------+-----------------+---------------+------
35241 | 58 | 699136 | 581839 |
1597 | 1663650 | 2205969940

Almost all checkpoints (99.8%) that happened are because of
checkpoint_timeout passing. Is this good or should I increaase my
checkpoint_segments?
During checkpoints, 699136 8K buffers were written out which is pretty low
(less than 1MB).

buffers allocated (2205969940 8K), 1663650 times a database backend
(probably the client itself) had to write a page in order to make space for
the new allocation. Buffer allocated seems to be too high than backend
buffers.

How to read more into the data?

Regards
Rohan