PostgreSQL Tools

Tools for inspection of various things in PostgreSQL servers.

Installation

To install this package, first make sure that you have a recent version of setuptools.

pip install --upgrade setuptools

After that, you can use pip to install the package directly from this directory:

pip install .

Running the tools

Show locking graph using `pg-lock-graph`

The tool pg-lock-graph will show a graph of all locks in a database as a graph with edges between processes and relations. It can be used to either get a full locking graph of the system (with the exception of the session that connects to read the locking graph), or limit the graph to only the nodes involved in a deadlock.

Restricting graph to deadlock

To print the subgraph(s) involving a deadlock, all edges that represents locks that are not granted are collected and the induced subgraph consisting of the vertices attached to those edges are built. To show just the subgraph of nodes involved in the deadlock, use the deadlock filter.

pg-lock-graph -f deadlock

Restrict graph to nodes of conflicts

To print the subgraph of nodes involved in a conflict, use the conflicts filter:

pg-lock-graph -f conflicts

This will print all nodes attached to the node having an edge that is not granted. This can be useful to narrow down the graph to just the part of the processes and relations involved in the conflict.

Use non-default socket location

If you have a source install, socket files are placed under /tmp so you can read from this by providing the directory as --host value and have PGDATA set correctly.

pg-lock-graph --host=/tmp

mkindahl/pg-tools