Operating system call fork:restart failed (error no. 22)

[Former Member]

I got this message (see title) on my ERP 6.0 EhP6 system this morning and did find in the dev_disp it was due to an error on a workprocess. Only problem was, in my system I have 46 process (total) but it complained on workprocess 47, which we don't have. Now I narrowed it down to being a dynamic workprocess which can be created in a busy system or when deadlocks come up.

But what I do not understand is the following: It does complain in the dev_disp ERROR => DpWpCreate: restart of work process 47 prohibited by parameter as4/wp_max_restart (22: Invalid argument) but that parameter is not set nor known by RZ11.

Parameter setting:

rdisp/wp_max_no is set as DEFAULT

rdisp/max_dynamic_wp_alive_time is not set

rdisp/wp_no_restricted has the default value of 0

as4/wp_max_restart not known so not set

rdisp/wp_no_dia   = 28

rdisp/wp_no_vb    = 6

rdisp/wp_no_vb2  = 1

rdisp/wp_no_enq  = 1

rdisp/wp_no_btc   = 7

rdisp/wp_no_spo  = 3

Further error message info according to dev_disp:

*** ERROR => DpWpCreate: restart of work process 47 prohibited by parameter as4/wp_max_restart (22: Invalid argument) [dpu
***LOG Q0I=> DpWpCreate, fork ( fork:restart 22) [dpuxdisp.c   978]
*** ERROR => DpWpDynCreate: DpWpCreate [dpuxdisp.c   320]
*** ERROR => DpWpStartWp: DpWpDynCreate [dpxxwp.c     3434]
*** ERROR => DpWpDynamicCheck: failed to start dynamic W47 (rc=-1) [dpxxwp.c     3403]
*** ERROR => DpWpCreate: restart of work process 47 prohibited by parameter as4/wp_max_restart (22: Invalid argument) [dpu
***LOG Q0I=> DpWpCreate, fork ( fork:restart 22) [dpuxdisp.c   978]
*** ERROR => DpWpDynCreate: DpWpCreate [dpuxdisp.c   320]
*** ERROR => DpWpStartWp: DpWpDynCreate [dpxxwp.c     3434]
*** ERROR => DpWpDynamicCheck: failed to start dynamic W47 (rc=-1) [dpxxwp.c     3403]

*** WARNING => DpHdlDeadWp: wp_adm slot for W47 has no pid [dpxxwp.c     1681]

I cannot find any deadlocks, nor errors on priv workprocess of full processes during the period the errors came up and needed a dynamic workprocess.

Does any one have an idea on why this is coming up? And what to do about it to not show in SM21 (better, not getting this error) as it will pop up to me from Solution Manager monitoring (mail alert).

Note this morning it pop uped during a time frame from 7 to 8:30.

[former_member182657 · Accepted solution]

Could refer SAP Note   884359 - iSeries: as4/wp_max_restart parameter in instance profile

Thanks,

[former_member185954]

Hello Christian,

I didn't know about dynamic process allocation, nice to read about it. I did a search on google with the parameter you mentioned and came up with the following thread from SDN

http://scn.sap.com/thread/351698

I think you should follow the advice provided in that thread.

Regards,

Siddhesh

[Former Member]

According to SAP:

I think there's some
confusion here!

The pase environment allows for AIX executables to run on an IBM I

environment. I would not be overly worried about seeing references to

it in the kernel.

The parameter as4/wp_max_restart can be set to 1000 safely, this

should prevent this from happening again.

I will change the parameter to the value given and hope that that will prevent it from happening again.

Ps seems that when doing a restart of the instance or the IPL the errors will be gone for a short while until it hits the default again.

[former_member182657]

Hi,

Only problem was, in my system I have 46 process (total) but it complained on workprocess 47, which we don't have.

As parameter rdisp/wp_max_no defines total number of WPs,and in your system it's set with value DEFAULT,so it's assuming total number of WP's as per below values of parameters in your system

rdisp/wp_no_dia + rdisp/wp_no_vb + rdisp/wp_no_vb2 + rdisp/wp_no_enq + rdisp/wp_no_btc + rdisp/wp_no_spo + rdisp/wp_no_restricted

Could you check by calculating by all & share.

Regards,

[Former Member]

Gaurav,

Outcome of rdisp/wp_no_dia (28) + rdisp/wp_no_vb (6) + rdisp/wp_no_vb2 (1) + rdisp/wp_no_enq (1) + rdisp/wp_no_btc (7) + rdisp/wp_no_spo (3) + rdisp/wp_no_restricted (0)is  46

In the ( ) the amount of processes is given.

(rdisp/wp_no_restricted has the default value of 0)

[manumohandas82]

Hi Christian ,

From 720 kernel there is dynamic work process allocation  ( The reason for attempt of increase in WP to 47 ) . Please let us know what kernel version you are in ?

Check 5.6 in the following Note and let us know what are the parameter settings

1636252 - Installing a 7.20 kernel in SAP Web AS 7.00/7.01/7.10/7.11

Thanks ,

Manu

[Former Member]

Manu

We are on kernel 7.21-300

Question remains, how to be able to 'resolve' the messages in SM21. Just the last hour again the messages pop up in sm21, but when I check all processes there is totally no need for extra work processes outside the normal amount set of work processes, in that period only 5 of the 46 were used.

[manumohandas82]

Did you miss this in the note

" Mind that rdisp/wp_max_no has the default value DEFAULT, which will add two unwanted dynamic processes if not set to the number of configured classical wp types"

*** WARNING => DpHdlDeadWp: wp_adm slot for W47 has no pid

Set rdisp/wp_max_no = 46 

Thanks ,

Manu

[Former Member]

Manu,

Is that kernel specific or only for nw7 and nw7.01 as we are running 7.31

Ps: Strange thing also is that another system we have has exactly the same kernel (even running on the same AS/400) and that system does not have any of these issues.

Message was edited by: Christian Bults

[manumohandas82]

The Note is specific to 7.0 and 7.01 running on 720/721 (Ext )

As you are in 7.31   ( Dont find any notes for this release on the dynamic wp allocation )  the note might not be relevant .

What is the value for the parameter  "as4/wp_max_restart "  can this be  set to 100 ?

Thanks ,

Manu

[Former Member]

According to the settings through notes on the as4/wp_max_restart when not specific set, the default will be taken so in our case default is 100.

Still for some reason it is only on this system and on the other system with same specs and settings, these errors do not come up.