As seen in database profiler for every client that connects we are seeing this query being run against the database which is MySQL 5.6 but this query never ever ends/loads.
If you manually try to run the query also it does not complete.The query is also very long.
SELECT dev.cs_id,
meci.master_id,
cim.ci_metric_id,
dev.dev_id
FROM CM_DEVICE dev
JOIN
CM_CONFIGURATION_ITEM ci ON ci.dev_id = dev.dev_id
JOIN
CM_CONFIGURATION_ITEM_METRIC cim ON cim.ci_id = ci.ci_id
LEFT JOIN
CM_CONFIG_ITEM_TO_MASTER meci ON meci.ci_id = ci.ci_id
WHERE 1=1
and (dev.dev_id IN ( 'D0ece9a1d810dd039c56b1c1d857603d0','D043BA3B5CB3B253453AA98BD717FF42A','D5323bd4bb84c2502a8ff28336cdb2710',
'DD522CCA63542EF4B7026ABF8DB712C63','D598ecd177fc8207b4d27a01fb1b921ad','DC81FD47B3BE5EA2C8074DB48AB4F5112','D9678ED856D87484ADB7651A50EBA3388',
'D3ECF2FF6DE9B39685AA6DB3A861C405C','D530F4BF1F779C61F59A795455F202D30','D22de76ebc89d542e8d24c3489bdcc9a3','D901DABBFDCE8C586F4D542F7EE6E22C0',
'DE009516F2166DDDFB32B02D257EE8247','DCC916CA4425393CCAF226214DE05C9A4','DEB452E298CEED4924C08C308C5127149','D4ef9284f9cf61aa4e9175f06f65a43ca','
'D3C1888E01ADD067068FA93675A1FB856',
...
...
...
'D330A86A8F4BC4D69FD3FCB1','D770A32F51484D51E03F5CA34DC6A999F','DBE43840EC35182B559D7EBE796F602B4','DD956A1E181F30ECBE61268D51F413EF1' ) )
Added a non-unique index for the column name ‘ci_id’ to the table ‘CM_CONFIG_ITEM_TO_MASTER’
create index cm_config_item_to_master_idx01 on cm_config_item_to_master(ci_id);
After this the USM was loading faster within 15-30 secs