wal file generation

[Sivakrishna Tungala <sivakrishna43@xxxxxxxxx>]

Hello,

i observed in my pg_xlog file wal files are generating  randomly(not in a sequence). is it an expected behaviour?  can anyone explain?

postgres=# select version();

                                                    version

----------------------------------------------------------------------------------------------------------------

 PostgreSQL 9.4.12 on x86_64-unknown-linux-gnu, compiled by gcc (GCC) 4.1.2 20080704 (Red Hat 4.1.2-55), 64-bit

Thanks & Regards,

T.Sivakrishna