Performance issue of deactivateLegacyPlugin()

[waviaei]

I have been investigating out client site, which seem to have few bottlenecks on the backend PHP processing, resulting in slow TTFB.

On my local site, using Blackfire as profiling tool, I found that deactivateLegacyPlugin() function of this plugin is one of the bottleneck, occupying up to around 15% (~450ms) of the php processing wall time.

I checked this by commeinting out add_action.

PublishPress-Checklists/core/Plugin.php

Line 54 in 9e8659c

add_action('init', [$this, 'deactivateLegacyPlugin']);

To be more exact, it is the core get_plugins() function, called inside deactivateLegacyPlugin() that is taking the time (and memory).

I feel get_plugins() can be improved to better utilize object cache -- it seems retrieved cache is only utilized only when $plugin_folder parameter is specified. And this particular site has around 70 plugins which doesn't help the situation.

Nevertheless, I think it is unnecessary to check legacy "publishpress-content-checklist" in this way, every time the site is accessed, even on the frontend when user is not logged in.

Possible Solution

Idea 1

I think checking the legacy plugin only needs to happen once, when this new plugin is activated. So this can be called once inside register_activation_hook ?

Idea 2

Put it inside is_admin(). Also add a filter something like publishpress_skip_legacy_check, which when return true, skip deactivateLegacyPlugin() to run. So if a developer is sure that this legacy plugin is not installed, we can skip the function.

Your Environment

• plugin ver 2.5.0 (I am aware this is not the latest, but 2.7.2 has the same code, so assuming same issue)
• multisite
• local environment is lando, with redis as persistant cache.