+Default: C<404>
+
+=item publicinbox.grokmanifest
+
+Controls the generation of a grokmirror-compatible gzipped JSON file
+at the top-level of the PSGI interface. You generally do not need to
+change this from the default.
+
+Valid values are:
+
+=over 8
+
+=item * match=domain
+- Only include inboxes with URLs which belong to the domain of
+the HTTP request. This is compatible with virtual hosting where
+several domains come from the same host.
+
+=item * all
+- All inboxes are present in C<manifest.js.gz>, regardless of domain.
+Only use this if you're serving HTTP requests in a domain-agnostic manner.
+
+=item * 404
+- C<manifest.js.gz> will only contain an empty JSON array.
+This does NOT affect C<$INBOX_URL/manifest.js.gz>, which will
+always contain all git repos used by the inbox at C<$INBOX_URL>
+
+=back
+
+Default: C<match=domain>
+
+=back
+
+=head2 NAMED LIMITER (PSGI)
+
+Named limiters are useful for preventing large inboxes from
+monopolizing (or overloading) the server. Since serving git
+clones (via L<git-http-backend(1)> can be memory-intensive for
+large inboxes, it makes sense to put large inboxes on a named
+limiter with a low max value; while smaller inboxes can use
+the default limiter.
+
+C<RLIMIT_*> keys may be set to enforce resource limits for
+a particular limiter.
+
+Default named-limiters are prefixed with "-". Currently,
+the "-cgit" named limiter is reserved for instances spawning
+cgit via C<publicinbox.cgitrc>
+
+=over 8
+
+=item publicinboxlimiter.<name>.max
+
+The maximum number of parallel processes for the given limiter.
+
+=item publicinboxlimiter.<name>.rlimitCore
+
+=item publicinboxlimiter.<name>.rlimitCPU
+
+=item publicinboxlimiter.<name>.rlimitData
+
+The maximum core size, CPU time, or data size processes run with the
+given limiter will use. This may be comma-separated to distinguish
+soft and hard limits. The word "INFINITY" is accepted as the
+RLIM_INFINITY constant (if supported by your OS).
+
+See L<setrlimit(2)> for more info on the behavior of RLIMIT_CORE,
+RLIMIT_CPU, and RLIMIT_DATA for you operating system.
+
+=back
+
+=head3 EXAMPLE WITH NAMED LIMITERS
+
+ ; big inboxes which require lots of memory to clone:
+ [publicinbox "big1"]
+ inboxdir = /path/to/big1
+ address = big1@example.com
+ httpbackendmax = big
+ [publicinbox "big2"]
+ inboxdir = /path/to/big2
+ address = big2@example.com
+ httpbackendmax = big
+
+ ; tiny inboxes which are easily cloned:
+ [publicinbox "tiny1"]
+ inboxdir = /path/to/tiny1
+ address = tiny1@example.com
+ [publicinbox "tiny2"]
+ inboxdir = /path/to/tiny2
+ address = tiny2@example.com
+
+ [publicinboxlimiter "big"]
+ max = 4
+
+In the above example, the "big1" and "big2" are limited to four
+parallel L<git-http-backend(1)> processes between them.
+
+However, "tiny1" and "tiny2" will share the default limiter
+which means there can be 32 L<git-http-backend(1)> processes
+between them.
+