[PATCH v6 3/3] workqueue: Adjust WQ_MAX_ACTIVE from 512 to 2048

From: Chen Ridong
Date: Tue Oct 08 2024 - 07:35:43 EST


From: Chen Ridong <chenridong@xxxxxxxxxx>

WQ_MAX_ACTIVE is currently set to 512, which was established approximately
15 yeas ago. However, with the significant increase in machine sizes and
capabilities, the previous limit of 256 concurrent tasks is no longer
sufficient. Therefore, we propose to increase WQ_MAX_ACTIVE to 2048.
and WQ_DFL_ACTIVE is 1024 now.

Signed-off-by: Chen Ridong <chenridong@xxxxxxxxxx>
---
Documentation/core-api/workqueue.rst | 4 ++--
include/linux/workqueue.h | 2 +-
2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Documentation/core-api/workqueue.rst b/Documentation/core-api/workqueue.rst
index 2b813f80ce39..e295835fc116 100644
--- a/Documentation/core-api/workqueue.rst
+++ b/Documentation/core-api/workqueue.rst
@@ -245,8 +245,8 @@ CPU which can be assigned to the work items of a wq. For example, with
at the same time per CPU. This is always a per-CPU attribute, even for
unbound workqueues.

-The maximum limit for ``@max_active`` is 512 and the default value used
-when 0 is specified is 256. These values are chosen sufficiently high
+The maximum limit for ``@max_active`` is 2048 and the default value used
+when 0 is specified is 1024. These values are chosen sufficiently high
such that they are not the limiting factor while providing protection in
runaway cases.

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index 59c2695e12e7..b0dc957c3e56 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -412,7 +412,7 @@ enum wq_flags {
};

enum wq_consts {
- WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
+ WQ_MAX_ACTIVE = 2048, /* I like 2048, better ideas? */
WQ_UNBOUND_MAX_ACTIVE = WQ_MAX_ACTIVE,
WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,

--
2.34.1