Reduce frequency of IPv6 probes in HostResolverImpl.
commitb8cdc219c478bde98b36acebcc859f1785a90119
authorsergeyu <sergeyu@chromium.org>
Thu, 14 May 2015 18:50:37 +0000 (14 11:50 -0700)
committerCommit bot <commit-bot@chromium.org>
Thu, 14 May 2015 18:50:43 +0000 (14 18:50 +0000)
tree69076f72534cf2c10600b73a18a155e3c9f8e236
parent9444f5f41b7cdea355dac95e0de83573b4e31a3d
Reduce frequency of IPv6 probes in HostResolverImpl.

Currently HostResolverImpl tries to probe IPv6 support for every
Resolve() request, i.e. very often. The probe is implemented using
a dummy UDP socket. This doesn't look efficient because IPv6 state
doesn't change often.

Also this change will decrease frequency of the crash in the linked bug.
In that bug the root cause is that on OSX system certificate library may
close recently created file descriptors it doesn't own. Not creating
dummy UDP sockets very often will help to avoid hitting this bug in the
OS very often.

BUG=481163

Review URL: https://codereview.chromium.org/1138833003

Cr-Commit-Position: refs/heads/master@{#329885}
net/dns/host_resolver_impl.cc
net/dns/host_resolver_impl.h
net/dns/host_resolver_impl_unittest.cc
net/log/test_net_log_entry.cc
net/log/test_net_log_entry.h