From: Andre Noll <maan@tuebingen.mpg.de>
Date: Thu, 7 Feb 2019 22:05:34 +0000 (+0100)
Subject: Introduce prune --disk-space.
X-Git-Tag: v1.0.1~1^2
X-Git-Url: http://git.tue.mpg.de/?a=commitdiff_plain;h=71a8073e6f18ccc21880a475af8d864279a960b8;p=dss.git

Introduce prune --disk-space.

The new option takes a mandatory argument of the set {check, high,
low}. The latter two make the command act as if disk space was
high/low without actually performing the check. This is mostly useful
for debugging.
---

diff --git a/dss.c b/dss.c
index e2ee7dd..4396e6e 100644
--- a/dss.c
+++ b/dss.c
@@ -1660,14 +1660,21 @@ static int com_prune(void)
 	struct snapshot *victim;
 	struct disk_space ds;
 	char *why;
+	bool try_hard;
 
 	lock_dss_or_die();
-	ret = get_disk_space(".", &ds);
-	if (ret < 0)
-		return ret;
-	log_disk_space(&ds);
+	switch (OPT_UINT32_VAL(PRUNE, DISK_SPACE)) {
+	case FDS_LOW: try_hard = true; break;
+	case FDS_HIGH: try_hard = false; break;
+	default:
+		ret = get_disk_space(".", &ds);
+		if (ret < 0)
+			return ret;
+		log_disk_space(&ds);
+		try_hard = disk_space_low(&ds);
+	}
 	dss_get_snapshot_list(&sl);
-	victim = find_removable_snapshot(&sl, disk_space_low(&ds), &why);
+	victim = find_removable_snapshot(&sl, try_hard, &why);
 	if (!victim) {
 		dss_msg("nothing to prune\n");
 		ret = 0;
diff --git a/dss.suite b/dss.suite
index 2719827..f9cf8af 100644
--- a/dss.suite
+++ b/dss.suite
@@ -466,6 +466,22 @@ caption = Subcommands
 
 		The subcommand fails if there is another dss "run" process.
 	[/description]
+	[option disk-space]
+		summary = act as if free disk space was high/low
+		arg_info = required_arg
+		arg_type = string
+		typestr = mode
+		values = {
+			FDS_CHECK = "check",
+			FDS_HIGH = "high",
+			FDS_LOW = "low"
+		}
+		default_val = check
+		[help]
+			By default, free disk space is checked and even regular snapshots
+			become candidates for removal if disk space is low. This option
+			overrides the result of the check.
+		[/help]
 [subcommand ls]
 	purpose = print the list of all snapshots
 	[description]