Posted on Jul 26

LiteSpeed vs Nginx for WordPress: 3 months of production benchmarks

#wordpress #performance #devops #benchmarking

TL;DR

Ran LiteSpeed Enterprise (LSWS) and Nginx side-by-side on identical VPS instances for 3 months, hosting the same 12 WordPress sites on each. LiteSpeed came out 33–45% faster on TTFB and moved 10/12 sites to a 90+ mobile PageSpeed score vs. 3/12 on Nginx. But ~80% of that advantage doesn't come from LSWS itself — it comes from the LSCache plugin, which also works with OpenLiteSpeed (free).

If you're deciding today: OpenLiteSpeed + LSCache is the pragmatic answer for most WordPress workloads.

The setup

Two identical VPS instances at the same Israeli data center:

Server A: LiteSpeed Enterprise 6.2 + LSCache 5.7 + PHP 8.2 (LSAPI) + CloudLinux
Server B: Nginx 1.24 + PHP 8.2 FPM + FastCGI cache + Redis object cache

Spec on each: 4 vCPU, 8 GB RAM, 100 GB NVMe, Ubuntu 22.04.

12 WordPress sites migrated to each (same versions, same plugin stack):

4 brochure sites (~50 pages, empty WooCommerce)
4 WooCommerce stores (500–2000 products)
4 Elementor blogs (500+ posts)

Load simulated with k6, 100 concurrent users, 30-min runs, realistic paths: home → category → product → cart → checkout.

Results — TTFB

Site type	Nginx	LiteSpeed	Δ
Brochure	142 ms	89 ms	−37%
WooCommerce empty	168 ms	112 ms	−33%
WooCommerce full	384 ms	210 ms	−45%
Blog	156 ms	98 ms	−37%

Results — RPS under load

Site type	Nginx	LiteSpeed	Δ
Brochure	340	520	+53%
WooCommerce empty	210	340	+62%
WooCommerce full	62	118	+90%
Blog	280	470	+68%

The gap widens with deeper PHP call trees. WooCommerce with a big catalog is nearly 2× faster on LSWS. Reason: LSAPI keeps a persistent worker pool that avoids PHP-FPM's cold-start overhead on complex requests.

Results — PageSpeed Insights (mobile)

Averages across all 12 sites, both stacks with the same image + Critical-CSS pipeline:

Metric	Nginx	LiteSpeed
LCP	2.4 s	1.6 s
FCP	1.7 s	1.1 s
CLS	0.03	0.03
TBT	240 ms	190 ms
Score	84	94

LiteSpeed moved 10/12 sites to 90+. Nginx got 3/12 there.

The plot twist

Three months in, I did one more test: installed OpenLiteSpeed (free, MIT license) + LSCache on Server B, in place of Nginx. Same 12 sites.

Metric	Nginx + FastCGI + Redis	OpenLiteSpeed + LSCache
TTFB (WooCommerce full)	384 ms	245 ms
PageSpeed (mobile)	84	92
License cost	$0	$0

~80% of LiteSpeed Enterprise's advantage came from the cache plugin, not the server. LSCache does four things no other WordPress cache plugin does at the same level:

QUIC.cloud CDN, free tier (built into the plugin)
Image optimization + WebP conversion in-process
Automatic Critical CSS generation
ESI edge-side includes — cache the shell of a page while keeping dynamic bits fresh (mini-carts, logged-in nav)

Recommended config

wp-config.php:

define('WP_CACHE', true);
define('WP_DEBUG', false);
define('WP_REDIS_HOST', '127.0.0.1');
define('WP_REDIS_PORT', 6379);
define('WP_REDIS_DATABASE', 0);
define('WP_POST_REVISIONS', 5);
define('AUTOSAVE_INTERVAL', 300);

Critical LSCache settings (Dashboard → LiteSpeed Cache):

Cache → General → Enable Cache: On
Cache → General → Cache Logged-in Users: Off (important)
Cache → Object → Object Cache: Redis
Cache → ESI → Enable ESI: On
CDN → QUIC.cloud CDN: On
Page Optimization → CSS: Combine + Minify + UCSS
Page Optimization → JS: Combine + Defer
Page Optimization → Images: Guest Optimization + Lazy Load
Page Optimization → HTML: Minify + DNS Prefetch

When Nginx still wins

API-only WordPress backends (headless) — Nginx + FPM has a tighter footprint for pure JSON responses.
Truly static traffic — landing pages, marketing sites with no dynamic content. Nginx + static file cache is unbeatable there.
Team that only knows Nginx — LSWS/OLS learning curve isn't worth it for a single box.

Eight-point WordPress performance checklist

curl -o /dev/null -s -w "%{time_starttransfer}\n" https://yoursite.com/ → TTFB under 200 ms
PageSpeed Insights on home + 3 product pages → LCP under 2.5 s
GTmetrix waterfall → cache HIT on every static asset
X-LiteSpeed-Cache: hit header on repeat requests (or equivalent for your cache)
Search Console → Core Web Vitals → 90%+ URLs "Good"
wp cli plugin list --status=active → under 25 active plugins
wp-admin → Site Health → no "Critical" issues
Redis object cache active — check "Cache Statistics" in your cache plugin

Bottom line

For WordPress in 2026:

On a shared host: LiteSpeed Enterprise + LSCache is the strongest option. Pay the license, forget about tuning.
On your own VPS: OpenLiteSpeed + LSCache gets you 90% of the way there for free.
Nginx: still the right call for API-only or ultra-static workloads, or if your team lives and breathes it.

Two days of proper LSCache config usually beats switching hosts.

I run Linux Hosting, an Israeli hosting provider running LiteSpeed Enterprise + LSCache across every plan. Comments and pushback welcome — this was measured on a real customer fleet, but every setup is different and I'd love to see other benchmarks.

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