Slow server restart with metadata index

[houjun]

What does this feature solve or improve?
The server takes a long time to restart even with just a few objects

./bin/pdc_server.exe &
./bin/vpicio
./bin/close_server
./bin/pdc_server.exe restart

...

==PDC_SERVER[0]: Server restarted from saved session, successfully loaded 1 containers, 8 objects, 0 regions...
[IDIOMS_Index_Recover_0] Timer to recover index = 21149388.0000 microseconds

==PDC_SERVER[0]: max cache size: 68719476736
==PDC_SERVER[0]: Successfully established connection to 0 other PDC servers
==PDC_SERVER[0]: total startup time = 21.336065
==PDC_SERVER[0]: Server ready!

Describe the solution you'd like
Make it faster

Describe alternatives you've considered

Additional Information

[houjun]

@zhangwei217245, can you look into this and see if the IDIOMS index can be recovered faster?