Frequently Asked Questions

Is mod_pagespeed still maintained?

Yes. We-Amp B.V. picked up where Google left off and actively maintains mod_pagespeed 1.1 with regular updates, security patches, and direct support.

What’s the difference between mod_pagespeed 1.1 and ModPageSpeed 2.0?

mod_pagespeed 1.1 is a drop-in continuation of the open-source project — same config, same filters, same in-process architecture. ModPageSpeed 2.0 is a ground-up rewrite in C++23 with a new external worker architecture. Both are actively maintained. 1.1 is best for existing deployments; 2.0 is best for new installations.

Do I need to change my config when upgrading from open-source?

No. All existing pagespeed directives work unchanged. Swap the binary, keep your config.

Which web servers does 1.1 support?

nginx (1.26+ as a dynamic module), Apache (drop-in replacement), IIS (native Windows Server module), and Envoy (HTTP filter).

What cache backend does 1.1 use?

Cyclone Cache — a fixed-size, lock-free, memory-mapped cache shared with ModPageSpeed 2.0. It replaces the old file-based cache. No configuration change required.

Which filters are enabled by default?

The CoreFilters set: add_head, combine_css, combine_javascript, convert_meta_tags, extend_cache, fallback_rewrite_css_urls, flatten_css_imports, inline_css, inline_import_to_link, inline_javascript, rewrite_css, rewrite_images, rewrite_javascript, rewrite_style_attributes_with_url. See Filter Selection for details.

Does it work with nginx 1.27 / Apache 2.4 / IIS 10?

Yes. mod_pagespeed 1.1 supports current stable releases of all four platforms.

What happens when my license expires?

mod_pagespeed stops optimizing and passes traffic through unmodified. Your web server continues to function normally. No downtime, no data loss.

How do I disable a specific filter?

Use DisableFilters in your config. For example: pagespeed DisableFilters combine_css; (nginx) or ModPagespeedDisableFilters combine_css (Apache). See Filter Selection.

Why isn’t mod_pagespeed rewriting my pages?

Check the response headers: X-Mod-Pagespeed (Apache) or X-Page-Speed (nginx). If the header is missing, mod_pagespeed is not running — verify the module is loaded and enabled. If it shows MISS, resources are being optimized on first request. If pages aren’t being rewritten, check that Content-Type is text/html and the response isn’t Cache-Control: no-transform. See Troubleshooting for more.

Can I use mod_pagespeed behind a CDN or reverse proxy?

Yes. mod_pagespeed works behind reverse proxies. For CDN integration, consider OptimizeForBandwidth mode which optimizes resources in-place without changing URLs. See Configuration for reverse proxy setup.

Where is the admin console?

Access it at /pagespeed_admin/ on your server. It shows active filters, cache stats, and lets you purge cached resources. See Admin Console for setup.

How do I flush or purge the cache?

Use the admin page: curl 'http://yoursite.com/pagespeed_admin/cache?purge=*' to purge everything, or replace * with a specific URL pattern. See Caching for details.

Where can I find the legacy open-source documentation?

The archived 1.0 docs are available at /1.0/.

How do I get support?

mod_pagespeed 1.1 includes direct support from the We-Amp team. Contact us with your question.