From 3ce222d89c816239ebd757583851079c66174f6d Mon Sep 17 00:00:00 2001
From: Patrick Donnelly <pdonnell@redhat.com>
Date: Fri, 21 Jul 2023 11:56:49 -0400
Subject: [PATCH] mds: adjust cap acquisition throttles

For production workloads, these defaults rarely help. Adjust
accordingly. For a steady state "find" workload, these new throttles
will prevent acquiring more than ~2300 caps/second which is quite
manageable with typical recall rates.

    -ln(0.5) / 30 * 100k = 2310

Fixes: https://tracker.ceph.com/issues/62114
Signed-off-by: Patrick Donnelly <pdonnell@redhat.com>
(cherry picked from commit f290ef9d0d2d09fb978d56c46be704c6efd45c43)

Conflicts:
	src/common/options/mds.yaml.in: trivial
---
 src/common/options.cc | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/common/options.cc b/src/common/options.cc
index 3f4527795f88e..7b0e4cf2b6c27 100644
--- a/src/common/options.cc
+++ b/src/common/options.cc
@@ -8430,13 +8430,13 @@ std::vector<Option> get_mds_options() {
     .set_long_description("This is the order of magnitude difference (in base 2) of the internal liveness decay counter and the number of capabilities the session holds. When this difference occurs, the MDS treats the session as quiescent and begins recalling capabilities."),
 
     Option("mds_session_cap_acquisition_decay_rate", Option::TYPE_FLOAT, Option::LEVEL_ADVANCED)
-    .set_default(10)
+    .set_default(30)
     .set_description("decay rate for session readdir caps leading to readdir throttle")
     .set_flag(Option::FLAG_RUNTIME)
     .set_long_description("The half-life for the session cap acquisition counter of caps acquired by readdir. This is used for throttling readdir requests from clients slow to release caps."),
 
     Option("mds_session_cap_acquisition_throttle", Option::TYPE_UINT, Option::LEVEL_ADVANCED)
-    .set_default(500000)
+    .set_default(100000)
     .set_description("throttle point for cap acquisition decay counter"),
 
     Option("mds_session_max_caps_throttle_ratio", Option::TYPE_FLOAT, Option::LEVEL_ADVANCED)