Files
scylladb/locator
Asias He 2a4582ab9f token_metadata: Speed up pending_endpoints_for
pending_endpoints_for is called frequently by
storage_proxy::create_write_response_handler when doing cql query.

Before this patch, each call to pending_endpoints_for involves
converting a multimap (std::unordered_multimap<range<token>,
inet_address>>) to map (std::unordered_map<range<token>,
std::unordered_set<inet_address>>).

To speed up the token to pending endpoint mapping search, a interval map
is introduced. It is faster than searching the map linearly and can
avoid caching the token/pending endpoint mapping.

With this patch, the operations per second drop during adding node
period gets much better.

Before:
45K to 10K

After:
45k to 38K

(The number is measured with the streaming code skipping to send data to
rule out the streaming factor.)

Refs: #1223
(cherry picked from commit 089734474b)
2016-05-20 13:03:31 +03:00
..