Cache Management
Shisho maintains three on-disk caches to speed up common operations. All three live under the directory set by the cache_dir config option (default /config/cache).
| Cache | What it stores | Notes |
|---|---|---|
| Downloads | Generated format conversions (e.g. kepub), files produced by plugins, and bulk-download zips. | Size is capped by download_cache_max_size_gb and evicted LRU-style automatically. |
| CBZ Pages | Page images extracted from CBZ files for the in-app reader. | Avoids re-extracting pages every time a CBZ is opened. |
| PDF Pages | JPEGs rendered from PDF pages for the in-app reader. | Avoids re-rendering pages; can grow large on image-heavy PDFs. |
Viewing cache usage
Admins can view the current size and file count of each cache at Settings → Cache (/settings/cache). The page requires the config:read permission.
Clearing caches
Each cache has its own Clear button. Clearing is safe — content is regenerated on next access — but can temporarily slow down affected operations (downloads, the PDF reader, etc.) while the cache rebuilds.
Clearing requires the config:write permission (admin-only by default). A confirmation dialog shows the number of files and total size that will be deleted before the action is performed.
When to clear
- Downloads: reclaim disk space after removing a plugin whose generated files should not be reused.
- CBZ Pages / PDF Pages: force the reader to re-extract or re-render after changing a config option that affects output (e.g.
pdf_render_dpiorpdf_render_quality).
See also: Configuration, Users and Permissions.