On 11/05/17 15:01, Simon Riggs wrote: > On 11 May 2017 at 08:32, Noah Misch <n...@leadboat.com> wrote: >> On Sun, Apr 23, 2017 at 01:10:32AM +0200, Petr Jelinek wrote: >>> The time based lag tracking commit [1] added interface for logging >>> progress of replication so that we can report lag as time interval >>> instead of just bytes. But the patch didn't contain patch for the >>> builtin logical replication. >>> >>> So I wrote something that implements this. >> >> This is listed as a PostgreSQL 10 open item, but the above makes it sound >> like >> a feature to consider for v11, not a defect in v10. Why is this an open >> item? > > It's an open item because at the time of the Lag Tracker commit it was > believed to be a single line of code that needed to be added to > Logical Replication to make it work with the Lag Tracker > functionality. It didn't make sense for me to add it while the LR code > was still being changed, even though we had code to do that. > > Petr's new patch is slightly longer and needed review and some minor > code to add pacing delay. > > My own delay in responding has been because of illness. You'll note > that I'd missed response on at least one other mail from you. > Apologies for that, it has set me back some way but I'm better now and > have caught up with other matters. Petr nudged me to look at this > thread again yesterday, so I had been looking at this over last few > days. > > Attached patch is Petr's patch, slightly rebased with added pacing > delay, similar to that used by HSFeedback. >
This looks reasonable. I would perhaps change: > + /* > + * Track lag no more than once per > WALSND_LOGICAL_LAG_TRACK_INTERVAL_MS > + */ to something like this for extra clarity: > + /* > + * Track lag no more than once per > WALSND_LOGICAL_LAG_TRACK_INTERVAL_MS > + * to avoid flooding the lag tracker on busy servers. > + */ -- Petr Jelinek http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
