# Schema Browser Slow after migration to 12c **URL:** \ **Category:** Toad for Oracle & DevOps Toolkit\ **Created:** [October 24, 2017, 2:12am UTC](https://forums.toadworld.com/t/schema-browser-slow-after-migration-to-12c/40138 "2017-10-24T02:12:48Z")\ **Posts on this page:** 1\ **Showing post:** 6
**Author:** ![JohnDorlon](https://sea1.discourse-cdn.com/quest/user_avatar/forums.toadworld.com/johndorlon/32/9997_2.png) [@JohnDorlon](https://forums.toadworld.com/u/JohnDorlon)\ **Post date:** [April 16, 2019, 12:33pm UTC](https://forums.toadworld.com/t/schema-browser-slow-after-migration-to-12c/40138/6 "2019-04-16T12:33:29Z")
Read this if you recently upgraded your database: > [@Toad 12.1 hangs for long when connecting to database via oracle connection manager](https://forums.toadworld.com/t/toad-12-1-hangs-for-long-when-connecting-to-database-via-oracle-connection-manager/46050/5): > > Hi, Thanks for the guidance, I worked with developer to trace the Toad session and below are the findings while connecting to PDB(pluggable) Oracle Database, there is a package (not DB stored package) which is being executed for every session whenever user connects from TOAD. While debugging , developer has found that ALL\_SYNONYMS is used in the package where it is taking long time to execute, and that block is being errored out with "ORA-03113 end-of-file on communication channel". select c… --- _[View the full topic](https://forums.toadworld.com/t/schema-browser-slow-after-migration-to-12c/40138)._