Hot_standby WAL archiving question

Hello all,
So I have been working on setting up an active/standby clustered postgresql 9.2 using corosync. The corosync documentation has me enable WAL archiving "archive_command = 'cp %p /db/data/postgresql/9.2/pg_archive/%f'"

I assume so that the secondary can catch up in async (log shipping) mode before going into sync (streaming) mode. But I am noticing as I push data through the DB, that my pg_archive keeps growing and I am worried about running out of disk space.

Per the postgresql documentation, I set "wal_keep_segments" but I believe this only effects the segments in the pg_xlog and not what the archive_command is processing.

So, since I am not keeping the archived WAL statements for long term use, is it safe to set "archive_cleanup_command = 'pg_archivecleanup /db/data/postgresql/9.2/pg_archive %r'" on the master? Also will the archive cleanup command even have effect? I only read about it being on slaves to clean-up what has already been processed.

Thank you!

-With kind regards,
Peter Brunnengräber