PostgreSQL Visualizers

Reading about PostgreSQL internals teaches you the words. Seeing them move teaches you the system. That is the jump these visualizers are built for. Click a buffer, insert a row, run two sessions against the same page, and watch the parts of Postgres that usually hide under SQL actually do their job.

PostgreSQL Shared Buffers Visualized

Interactive visualization of PostgreSQL's buffer pool, clock sweep eviction, and hash table lookups.

Inside the 8KB Page: PostgreSQL Page Layout Visualized

Interactive visualization of PostgreSQL's 8KB page: header, line pointers, free space, and tuple data.

PostgreSQL MVCC Visualized

Interactive visualization of PostgreSQL's MVCC: xmin, xmax, snapshots, two concurrent sessions, and VACUUM reclaim.

PostgreSQL HOT Updates and Page Pruning Visualized

Interactive visualization of HOT updates and page pruning. Watch ctid chains form on a single page, see HOT_UPDATED and HEAP_ONLY flags flip, and trigger pruning to reclaim dead chain members.

PostgreSQL TOAST Visualized

Interactive visualization of PostgreSQL's TOAST machinery. Watch wide values get compressed, sliced into chunks, and relocated from the main heap into pg_toast, with the four storage strategies and two compression methods as live controls.