diff --git a/sys/kern/uipc_ktls.c b/sys/kern/uipc_ktls.c
--- a/sys/kern/uipc_ktls.c
+++ b/sys/kern/uipc_ktls.c
@@ -495,7 +495,7 @@
 		ktls_buffer_zone = uma_zcache_create("ktls_buffers",
 		    roundup2(ktls_maxlen, PAGE_SIZE), NULL, NULL, NULL, NULL,
 		    ktls_buffer_import, ktls_buffer_release, NULL,
-		    UMA_ZONE_FIRSTTOUCH);
+		    UMA_ZONE_FIRSTTOUCH | UMA_ZONE_NOTRIM);
 	}
 
 	/*
diff --git a/sys/vm/uma.h b/sys/vm/uma.h
--- a/sys/vm/uma.h
+++ b/sys/vm/uma.h
@@ -252,6 +252,7 @@
 #define	UMA_ZONE_SECONDARY	0x0200	/* Zone is a Secondary Zone */
 #define	UMA_ZONE_NOBUCKET	0x0400	/* Do not use buckets. */
 #define	UMA_ZONE_MAXBUCKET	0x0800	/* Use largest buckets. */
+#define	UMA_ZONE_NOTRIM		0x1000	/* Don't trim this zone */
 #define	UMA_ZONE_CACHESPREAD	0x2000	/*
 					 * Spread memory start locations across
 					 * all possible cache lines.  May
diff --git a/sys/vm/uma_core.c b/sys/vm/uma_core.c
--- a/sys/vm/uma_core.c
+++ b/sys/vm/uma_core.c
@@ -1222,7 +1222,7 @@
 
 trim:
 	/* Trim caches not used for a long time. */
-	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0) {
+	if ((zone->uz_flags & (UMA_ZONE_UNMANAGED | UMA_ZONE_NOTRIM)) == 0) {
 		for (int i = 0; i < vm_ndomains; i++) {
 			if (bucket_cache_reclaim_domain(zone, false, false, i) &&
 			    (zone->uz_flags & UMA_ZFLAG_CACHE) == 0)
@@ -5306,8 +5306,13 @@
 	struct uma_reclaim_args *args;
 
 	args = arg;
-	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) == 0)
-		uma_zone_reclaim_domain(zone, args->req, args->domain);
+	if ((zone->uz_flags & UMA_ZONE_UNMANAGED) != 0)
+		return;
+	if ((args->req == UMA_RECLAIM_TRIM) &&
+	    (zone->uz_flags & UMA_ZONE_NOTRIM) !=0)
+		return;
+
+	uma_zone_reclaim_domain(zone, args->req, args->domain);
 }
 
 /* See uma.h */