The Header Cache Compression Feature can be used for speeding up the loading of large mailboxes. Also the space used on disk can be shrunk by about 50% - depending on the compression method being used.
The implementation sits on top of the header caching functions. So the header cache compression can be used together with all available database backends.
Table 19.1. Header Cache Compression Variables
Name | Type | Default |
---|---|---|
header_cache_compress_method
|
string | (empty) |
header_cache_compress_level
|
number |
1
|
The
header_cache_compress_method
can be
(empty)
- which means, that no header cache compression should be used. But when set to
lz4
,
zlib
or
zstd
- then the compression is turned on.
The
header_cache_compress_level
defines the compression level, which should be used together with the selected
header_cache_compress_method
. Here is an overview of the possible settings:
Table 19.2. Header Cache Compression Methods and it's Levels
Method Name | Min | Max |
---|---|---|
lz4
|
1 | 12 |
zlib
|
1 | 9 |
zstd
|
1 | 22 |
# Example NeoMutt config file for the header cache compression feature. # -------------------------------------------------------------------------- # VARIABLES – shown with their default values # -------------------------------------------------------------------------- set header_cache_compress_level = 1 set header_cache_compress_method = "" # vim: syntax=neomuttrc