From 44eb3e3f973a641b5edffdda1d688c75c9bb9b0a Mon Sep 17 00:00:00 2001
From: Agniva De Sarker <agnivade@yahoo.co.in>
Date: Thu, 10 Dec 2020 19:51:52 +0530
Subject: [PATCH] MM-31326: Fix Striped LRU to have minimum of 1 bucket
 (#16531)

* MM-31326: Fix Striped LRU to have minimum of 1 bucket

https://mattermost.atlassian.net/browse/MM-31236

```release-note
NONE
```

* Using a maxInt function
---
 app/server.go                  | 11 +++++++++--
 store/localcachelayer/layer.go | 11 +++++++++--
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/app/server.go b/app/server.go
index 9ddf68cc0d..92ab55d3cc 100644
--- a/app/server.go
+++ b/app/server.go
@@ -291,7 +291,7 @@ func NewServer(options ...Option) (*Server, error) {
 	if s.sessionCache, err = s.CacheProvider.NewCache(&cache.CacheOptions{
 		Size:           model.SESSION_CACHE_SIZE,
 		Striped:        true,
-		StripedBuckets: runtime.NumCPU() - 1,
+		StripedBuckets: maxInt(runtime.NumCPU()-1, 1),
 	}); err != nil {
 		return nil, errors.Wrap(err, "Unable to create session cache")
 	}
@@ -303,7 +303,7 @@ func NewServer(options ...Option) (*Server, error) {
 	if s.statusCache, err = s.CacheProvider.NewCache(&cache.CacheOptions{
 		Size:           model.STATUS_CACHE_SIZE,
 		Striped:        true,
-		StripedBuckets: runtime.NumCPU() - 1,
+		StripedBuckets: maxInt(runtime.NumCPU()-1, 1),
 	}); err != nil {
 		return nil, errors.Wrap(err, "Unable to create status cache")
 	}
@@ -564,6 +564,13 @@ func NewServer(options ...Option) (*Server, error) {
 	return s, nil
 }
 
+func maxInt(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
 func (s *Server) RunJobs() {
 	if s.runjobs {
 		s.Go(func() {
diff --git a/store/localcachelayer/layer.go b/store/localcachelayer/layer.go
index 34b796cdd8..179000e79c 100644
--- a/store/localcachelayer/layer.go
+++ b/store/localcachelayer/layer.go
@@ -133,7 +133,7 @@ func NewLocalCacheLayer(baseStore store.Store, metrics einterfaces.MetricsInterf
 		DefaultExpiry:          ROLE_CACHE_SEC * time.Second,
 		InvalidateClusterEvent: model.CLUSTER_EVENT_INVALIDATE_CACHE_FOR_ROLES,
 		Striped:                true,
-		StripedBuckets:         runtime.NumCPU() - 1,
+		StripedBuckets:         maxInt(runtime.NumCPU()-1, 1),
 	}); err != nil {
 		return
 	}
@@ -271,7 +271,7 @@ func NewLocalCacheLayer(baseStore store.Store, metrics einterfaces.MetricsInterf
 		DefaultExpiry:          USER_PROFILE_BY_ID_SEC * time.Second,
 		InvalidateClusterEvent: model.CLUSTER_EVENT_INVALIDATE_CACHE_FOR_PROFILE_BY_IDS,
 		Striped:                true,
-		StripedBuckets:         runtime.NumCPU() - 1,
+		StripedBuckets:         maxInt(runtime.NumCPU()-1, 1),
 	}); err != nil {
 		return
 	}
@@ -319,6 +319,13 @@ func NewLocalCacheLayer(baseStore store.Store, metrics einterfaces.MetricsInterf
 	return
 }
 
+func maxInt(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
 func (s LocalCacheStore) Reaction() store.ReactionStore {
 	return s.reaction
 }