How To Enhance The performance of the STMS import Queue ?

Dear Experts,

We have ERP system SAP NW 7,31 SP 05. Our Platform is AS/400 and The Database Is DB2.

We are facing performance issues with the STMS transaction it takes 5Min to refresh and alot time to import, and even more in the busy hours of the system.

My Questions are :

1- is there any tips to fine tune the performance of the STMS ?

2- Our Dev system have over 400 requests that already have been imported in the PRO system, if i delete them from DEV queue

will it effect the PRO system ?

And if you know any tips or tricks please share with me

Many Thanks In Advance..

Regards,

Ahmed Salam