journal: rework vacuuming logic

Implement a maximum limit on number of journal files to keep around.
Enforcing a limit is useful on this since our performance when viewing
pays a heavy penalty for each journal file to interleve. This setting is
turned on now by default, and set to 100.

Also, actully implement what 348ced909724a1331b85d57aede80a102a00e428
promised: use whatever we find on disk at startup as lower bound on how
much disk space we can use. That commit introduced some provisions to
implement this, but actually never did.

This also adds "journalctl --vacuum-files=" to vacuum files on disk by
their number explicitly.

1 files changed, 6 insertions, 3 deletions

diff --git a/src/journal/journald-server.h b/src/journal/journald-server.h
index d954c5190d..535c0ab9ab 100644
--- a/src/journal/journald-server.h
+++ b/src/journal/journald-server.h
@@ -100,8 +100,9 @@ typedef struct Server {
         unsigned n_forward_syslog_missed;
         usec_t last_warn_forward_syslog_missed;
 
-        uint64_t cached_available_space;
-        usec_t cached_available_space_timestamp;
+        uint64_t cached_space_available;
+        uint64_t cached_space_limit;
+        usec_t cached_space_timestamp;
 
         uint64_t var_available_timestamp;
 
@@ -141,6 +142,8 @@ typedef struct Server {
         char *cgroup_root;
 } Server;
 
+#define SERVER_MACHINE_ID(s) ((s)->machine_id_field + strlen("_MACHINE_ID="))
+
 #define N_IOVEC_META_FIELDS 20
 #define N_IOVEC_KERNEL_FIELDS 64
 #define N_IOVEC_UDEV_FIELDS 32
@@ -166,7 +169,7 @@ void server_fix_perms(Server *s, JournalFile *f, uid_t uid);
 int server_init(Server *s);
 void server_done(Server *s);
 void server_sync(Server *s);
-void server_vacuum(Server *s);
+int server_vacuum(Server *s, bool verbose, bool patch_min_use);
 void server_rotate(Server *s);
 int server_schedule_sync(Server *s, int priority);
 int server_flush_to_var(Server *s);