From 6e12aca53b1be1cc29e71091f819eebf26555bd7 Mon Sep 17 00:00:00 2001
From: Vitaliy Filippov <vitalif@yourcmc.ru>
Date: Fri, 26 Nov 2021 23:05:37 +0300
Subject: [PATCH] Remove the total PG count restriction in optimize_change
 which was leading to unfeasible problems sometimes

---
 mon/lp-optimizer.js             |  5 -----
 mon/test-optimize-unfeasible.js | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 5 deletions(-)
 create mode 100644 mon/test-optimize-unfeasible.js

diff --git a/mon/lp-optimizer.js b/mon/lp-optimizer.js
index 0d47af87..cd9a88cd 100644
--- a/mon/lp-optimizer.js
+++ b/mon/lp-optimizer.js
@@ -293,11 +293,6 @@ async function optimize_change({ prev_pgs: prev_int_pgs, osd_tree, pg_size = 3,
     lp += 'max: '+all_pg_names.map(pg_name => (
         prev_weights[pg_name] ? `${pg_size+1}*add_${pg_name} - ${pg_size+1}*del_${pg_name}` : `${pg_size+1-move_weights[pg_name]}*${pg_name}`
     )).join(' + ')+';\n';
-    lp += all_pg_names
-        .map(pg_name => (prev_weights[pg_name] ? `add_${pg_name} - del_${pg_name}` : `${pg_name}`))
-        .join(' + ')+' = '+(pg_count
-            - Object.keys(prev_weights).reduce((a, old_pg_name) => (a + (all_pgs_hash[old_pg_name] ? prev_weights[old_pg_name] : 0)), 0)
-        )+';\n';
     for (const osd in pg_per_osd)
     {
         if (osd !== NO_OSD)
diff --git a/mon/test-optimize-unfeasible.js b/mon/test-optimize-unfeasible.js
new file mode 100644
index 00000000..c632f9cc
--- /dev/null
+++ b/mon/test-optimize-unfeasible.js
@@ -0,0 +1,33 @@
+// Copyright (c) Vitaliy Filippov, 2019+
+// License: VNPL-1.1 (see README.md for details)
+
+const LPOptimizer = require('./lp-optimizer.js');
+
+const osd_tree = {
+    100: {
+        1: 0.1,
+        2: 0.1,
+        3: 0.1,
+    },
+    200: {
+        4: 0.1,
+        5: 0.1,
+        6: 0.1,
+    },
+};
+
+async function run()
+{
+    let res;
+    console.log('256 PGs, 3+3 OSDs, size=2');
+    res = await LPOptimizer.optimize_initial({ osd_tree, pg_size: 2, pg_count: 256 });
+    LPOptimizer.print_change_stats(res, false);
+
+    // Should NOT fail with the "unfeasible or unbounded" exception
+    console.log('\nRemoving osd.2');
+    delete osd_tree[100][2];
+    res = await LPOptimizer.optimize_change({ prev_pgs: res.int_pgs, osd_tree, pg_size: 2 });
+    LPOptimizer.print_change_stats(res, false);
+}
+
+run().catch(console.error);