added cache size measurement code

[google-cla[bot]]

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[ssbr]

BTW don't forget to rewrite the commit to use your @google.com email to resolve CLA bot's concerns.

[negara]

@ssbr @sivachandra @mmdriley Made changes to the code based on the PR comments and also modified code to report maximum latency instead of the average time. Please review the new code as it is a mixed of the new work and PR conversations.