Small Datum: Postgres vs tproc-c on a small server

Thursday, January 8, 2026

Postgres vs tproc-c on a small server

This is my first post with results from tproc-c using HammerDB. This post has results for Postgres.

tl;dr - across 8 workloads (low and medium concurrency, cached database to IO-bound)

there might be a regression for Postgres 14.20 and 15.15 in one workload
there are improvements, some big, for Postgres 17 and 18 in most workloads

Builds, configuration and hardware

I compiled Postgres from source using -O2 -fno-omit-frame-pointer for versions 12.22, 13.23, 14.20, 15.15, 16.11, 17.7 and 18.1.

The server is an ASUS ExpertCenter PN53 with an AMD Ryzen 7 7735HS CPU, 8 cores, SMT disabled, and 32G of RAM. Storage is one NVMe device for the database using ext-4 with discard enabled. The OS is Ubuntu 24.04. More details on it are here.

For versions prior to 18, the config file is named conf.diff.cx10a_c8r32 and they are as similar as possible and here for versions 12, 13, 14, 15, 16 and 17.

For Postgres 18 the config file is named conf.diff.cx10b_c8r32 and adds io_mod='sync' which matches behavior in earlier Postgres versions.

Benchmark

The benchmark is tproc-c from HammerDB. The tproc-c benchmark is derived from TPC-C.

The benchmark was run for several workloads:

vu=1, w=100 - 1 virtual user, 100 warehouses
vu=6, w=100 - 6 virtual users, 100 warehouses
vu=1, w=1000 - 1 virtual user, 1000 warehouses
vu=6, w=1000 - 6 virtual users, 1000 warehouses
vu=1, w=2000 - 1 virtual user, 2000 warehouses
vu=6, w=2000 - 6 virtual users, 2000 warehouses
vu=1, w=4000 - 1 virtual user, 4000 warehouses
vu=6, w=4000 - 6 virtual users, 4000 warehouses

The benchmark is run by this script which depends on scripts here.

stored procedures are enabled
partitioning is used for when the warehouse count is >= 1000
a 5 minute rampup is used
then performance is measured for 120 minutes

Results

All artifacts from the tests are here. A spreadsheet with the charts and numbers is here.

My analysis at this point is simple -- I only consider average throughput. Eventually I will examine throughput over time and efficiency (CPU and IO).

On the charts that follow y-axis starts at 0.9 to improve readability. The y-axis shows relative throughput. There might be a regression when the relative throughput is less than 1.0. There might be an improvement when it is > 1.0. The relative throughput is: