From f674cb5ecc9da3b0cfba21c5b334934401d27905 Mon Sep 17 00:00:00 2001
From: Peter Hoeg <peter@hoeg.com>
Date: Wed, 3 Jan 2018 12:38:29 +0800
Subject: [PATCH] kernel: enable writeback throttling to avoid IO queues
 filling up

---
 pkgs/os-specific/linux/kernel/common-config.nix | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/pkgs/os-specific/linux/kernel/common-config.nix b/pkgs/os-specific/linux/kernel/common-config.nix
index 64f8163369b..5fc22736d7f 100644
--- a/pkgs/os-specific/linux/kernel/common-config.nix
+++ b/pkgs/os-specific/linux/kernel/common-config.nix
@@ -370,6 +370,15 @@ with stdenv.lib;
     MICROCODE_AMD_EARLY y
   ''}
 
+  ${optionalString (versionAtLeast version "4.10") ''
+    # Write Back Throttling
+    # https://lwn.net/Articles/682582/
+    # https://bugzilla.kernel.org/show_bug.cgi?id=12309#c655
+    BLK_WBT y
+    BLK_WBT_SQ y
+    BLK_WBT_MQ y
+  ''}
+
   # Misc. options.
   8139TOO_8129 y
   8139TOO_PIO n # PIO is slower