fitz-pgserver 0.1.5

Fork of pgserver with Windows crash recovery fix - self-contained PostgreSQL for Python apps

fitz-pgserver

Fork of pgserver with Windows crash recovery fix.

Why this fork?

On Windows, when PostgreSQL crashes or is killed (e.g., via Ctrl+C), the recovery process can fail with a "sharing violation" error on the log file. This happens because:

1. pg_ctl -l logfile start opens the log file for writing
2. postgres subprocess starts and does crash recovery
3. During recovery, postgres tries to fsync the entire pgdata directory
4. This includes the log file that pg_ctl still has open → sharing violation
5. postgres retries for 30 seconds before proceeding

The Fix

Put the log file in the system temp directory (outside pgdata):

# Before (pgserver):
self.log = self.pgdata / 'log'

# After (fitz-pgserver):
temp_dir = Path(tempfile.gettempdir())
self.log = temp_dir / f'pgserver_log.{uuid.uuid4().hex[:8]}'

By putting the log file outside pgdata, postgres doesn't try to fsync it during recovery, avoiding the sharing violation entirely.

Installation

pip install fitz-pgserver

Usage

Drop-in replacement for pgserver:

# Instead of: import pgserver
import fitz_pgserver as pgserver

db = pgserver.get_server("./my_pgdata")
uri = db.get_uri()
# Use uri with psycopg, SQLAlchemy, etc.

Performance

Scenario	pgserver	fitz-pgserver
Normal startup	~2s	~2s
First-time init	~10-13s	~10-13s
Crash recovery	~33s (data preserved but slow)	~1-2s (28x faster)

The massive improvement in crash recovery is because we avoid the 30-second sharing violation retry loop.

License

Apache 2.0 (same as original pgserver)

Credits

Original pgserver by Oscar Moll.