Re: [PATCH] Make ENOSPC not fatal in semaphore creation

[Mikhail]

On Sun, Oct 17, 2021 at 10:52:38AM -0400, Tom Lane wrote:
> I am, however, concerned that this'll just trade off one hazard for
> another.  Instead of a risk of failing with ENOSPC (which the DBA
> can fix), we'll have a risk of kneecapping some other process at
> random (which the DBA can do nothing to prevent).

I tend to agree, and along with semas patch would like to suggest error
message improvement, it would have saved me about half a day of digging.
Tested on OpenBSD 7.0.

I'm not a native speaker though, so grammar need to be checked.

diff --git a/src/backend/port/sysv_sema.c b/src/backend/port/sysv_sema.c
index 21c883ba9a..b84f70b5e2 100644
--- a/src/backend/port/sysv_sema.c
+++ b/src/backend/port/sysv_sema.c
@@ -133,7 +133,10 @@ InternalIpcSemaphoreCreate(IpcSemaphoreKey semKey, int 
numSems)
                                                 "respective kernel parameter.  
Alternatively, reduce PostgreSQL's "
                                                 "consumption of semaphores by 
reducing its max_connections parameter.\n"
                                                 "The PostgreSQL documentation 
contains more information about "
-                                                "configuring your system for 
PostgreSQL.") : 0));
+                                                "configuring your system for 
PostgreSQL.\n"
+                                                "If server has crashed 
previously there may be resources left "
+                                                "after it - take a look at 
ipcs(1) and ipcrm(1) man pages to see "
+                                                "how to remove them.") : 0));
        }
 
        return semId;