On 5/1/18 12:27, Stas Kelvich wrote: > Clock-SI is described in [5] and here I provide a small overview, which > supposedly should be enough to catch the idea. Assume that each node runs > Commit > Sequence Number (CSN) based visibility: database tracks one counter for each > transaction start (xid) and another counter for each transaction commit (csn). > In such setting, a snapshot is just a single number -- a copy of current CSN > at > the moment when the snapshot was taken. Visibility rules are boiled down to > checking whether current tuple's CSN is less than our snapshot's csn. Also it > worth of mentioning that for the last 5 years there is an active proposal to > switch Postgres to CSN-based visibility [6].
But that proposal has so far not succeeded. How are you overcoming the reasons for that? -- Peter Eisentraut http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
