Forms Process (FRMWEB) Consumes 100% of CPU in Oracle Applications
Cause:
The root cause of the issue is that returning rows from LOVs in core forms causes the forms process to grow up into memory depending on the number of rows returned.
When an end user login to forms and start working with LOV within core forms sometimes and according to the search criteria that the user will provide to filter the results in LOV, it may fetch huge numbers of records in which causes the frmweb process to grow very large, and in extreme cases this can even lock up the current process or even the whole machine.
So when executing a LOV query, every row is fetched into memory on the middle tier, the frmweb process can get extremely large, and the larger it gets the more likely it is to start paging.
Eventually it starts consuming excessive CPU just paging the process in and out of memory, which is probably what you can see here in this case as the amount of memory consumed when the LOV records are fetched into memory obviously depends on the amount of data in each record.
Please be aware:
This solution has been identifed for a Forms Configuration using the SOCKET mode, which is not the default mode in EBS R12. You can use the solution also for the SERVLET mode - in this case you have to add the FORMS_RECORD_GROUP_MAX to the default.env file.
Solution:
To implement the solution, please execute the following steps:
1. Stop all services on the middle tier.
2. Set following forms environment variables:
FORMS_RECORD_GROUP_MAX to 10000 or if that proves too restrictive, increase it to 20000 or 30000.
FORMS_CATCHTERM=0
In order to set the above forms variables so next time autoconfig run does not override those values, do the following steps.
1- For Forms Variable "FORMS_CATCHTERM" the context vairable name is: "s_forms_catchterm" and you can update the context file located in ($INST_TOP/appl/admin/)
2- For other forms variable "FORMS_RECORD_GROUP_MAX" there is no variable defined in Autoconfig for that one and have to customize the autoconfig for the forms variables to set that environment as following:
a) Go to the autoconfig Template folder:
$cd $AD_TOP/admin/template
b) Create new directory named (custom)
$ mkdir custom
c) Make sure that new directory has same file permissions as ($AD_TOP/admin/template)
d) Copy the following autoconfig template to the new custom directory:
$cp $AD_TOP/admin/template/APPLSYS_ux.env $AD_TOP/admin/template/custom/APPLSYS_ux.env
e) Edit the file copied file under custom directory and add the following 2 lines at the end of section:
####################################
# Oracle Forms environment variables
####################################
FORMS_RECORD_GROUP_MAX=10000
export FORMS_RECORD_GROUP_MAX
f) Save and exit from the file.
g) Next time autoconfig run, it will read the custom directory and check for any customizations there.
3. Run Autoconfig on the middle tier and make sure it is completed successfully.
4. Startup all services.
5. Monitor the forms process to see its CPU usage, and you will see that form process usage is reduced and not causing any more CPU consumption up to 100% as before.
6. Migrate the solution as appropriate to other environments.
Reference metalink Doc ID 1382442.1
Cause:
The root cause of the issue is that returning rows from LOVs in core forms causes the forms process to grow up into memory depending on the number of rows returned.
When an end user login to forms and start working with LOV within core forms sometimes and according to the search criteria that the user will provide to filter the results in LOV, it may fetch huge numbers of records in which causes the frmweb process to grow very large, and in extreme cases this can even lock up the current process or even the whole machine.
So when executing a LOV query, every row is fetched into memory on the middle tier, the frmweb process can get extremely large, and the larger it gets the more likely it is to start paging.
Eventually it starts consuming excessive CPU just paging the process in and out of memory, which is probably what you can see here in this case as the amount of memory consumed when the LOV records are fetched into memory obviously depends on the amount of data in each record.
Please be aware:
This solution has been identifed for a Forms Configuration using the SOCKET mode, which is not the default mode in EBS R12. You can use the solution also for the SERVLET mode - in this case you have to add the FORMS_RECORD_GROUP_MAX to the default.env file.
Solution:
To implement the solution, please execute the following steps:
1. Stop all services on the middle tier.
2. Set following forms environment variables:
FORMS_RECORD_GROUP_MAX to 10000 or if that proves too restrictive, increase it to 20000 or 30000.
FORMS_CATCHTERM=0
In order to set the above forms variables so next time autoconfig run does not override those values, do the following steps.
1- For Forms Variable "FORMS_CATCHTERM" the context vairable name is: "s_forms_catchterm" and you can update the context file located in ($INST_TOP/appl/admin/)
2- For other forms variable "FORMS_RECORD_GROUP_MAX" there is no variable defined in Autoconfig for that one and have to customize the autoconfig for the forms variables to set that environment as following:
a) Go to the autoconfig Template folder:
$cd $AD_TOP/admin/template
b) Create new directory named (custom)
$ mkdir custom
c) Make sure that new directory has same file permissions as ($AD_TOP/admin/template)
d) Copy the following autoconfig template to the new custom directory:
$cp $AD_TOP/admin/template/APPLSYS_ux.env $AD_TOP/admin/template/custom/APPLSYS_ux.env
e) Edit the file copied file under custom directory and add the following 2 lines at the end of section:
####################################
# Oracle Forms environment variables
####################################
FORMS_RECORD_GROUP_MAX=10000
export FORMS_RECORD_GROUP_MAX
f) Save and exit from the file.
g) Next time autoconfig run, it will read the custom directory and check for any customizations there.
3. Run Autoconfig on the middle tier and make sure it is completed successfully.
4. Startup all services.
5. Monitor the forms process to see its CPU usage, and you will see that form process usage is reduced and not causing any more CPU consumption up to 100% as before.
6. Migrate the solution as appropriate to other environments.
Reference metalink Doc ID 1382442.1
