On Wed, Sep 20, 2017 at 3:14 PM, Meel Velliste <meel@xxxxxxxxxxxx> wrote: > From what I understand about logical decoding, there is no limit to how many > log entries will be retained by the server if nobody reads them from the > logical slot. This means that a client that fails to read from the slot has > the power to bring down the master database because the server's disk will > get full at which point all subsequent write operations will fail and even > read operations will fail because they too need temporary space. Even the > underlying operating system may be affected as it too may need temporary > disk space to carry out its basic functions. Monitoring is a mandatory part of the handling of replication slots. One possible solution is to use a background worker that scans slots causing bloat in pg_xlog and to automatically get rid of them so as the primary is preserved from any crash. Note that advancing a slot is doable for a physical slot, but advancing a logical slot is trickier (not sure if that's doable actually but Andres can comment on that) because it involves being sure that the catalog_xmin is still preserved so as past logical changes can be looked at consistently. -- Michael -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
