1503296 - Getting into state where network stops working (s/network/notwork/)

Status: RESOLVED DUPLICATE of bug 1484947

(Core :: Security: PSM, defect)

Description

[Steve Fink [:sfink] [:s:]]

For the last few days, I'll start up Nightly and things will work fine for a while (~30min or so), then all new network transfers stop completing. That includes URLs I type in, as well as things like the update check. The CPU utilization is very high (>100% of 1 core). Everything else appears to be functional.

I have had some problems with my home DSL recently, and initially I was blaming that, but Chrome is fine at these times. And restarting Firefox fixes it, for a while.

I have a NordVPN extension, which I disabled before restarting (so that I could file this bug.) I don't know if it's related or not. I'll report back if it seems like the problem has gone away, though I'm already seeing https://fitzgen.github.io/bugzilla-todos/ spinning forever in a pinned tab (I'm not confident that's the same problem, though.)

I captured a profile in this state, but I can't share it because it never finished symbolication (because it required the network). I attempted to save it to a file, but it looks like it never managed to write to disk either.

I took a perf recording (this is on Linux, Fedora 27). It shows tons of time in mozilla::net::nsHttpTransaction::WriteSegments. I'll paste that below.

Active addons:

Firefox Multi-Account Containers
Gecko Profiler
Tab Stats
Tree Style Tab
uBlock Origin
User-Agent Switcher

--- perf tree rooted at WriteSegments ---

-   70.80%     5.21%  Socket Thread    libxul.so                   [.] mozilla::net::nsHttpTransaction::WriteSegments  ▒
   - 65.59% mozilla::net::nsHttpTransaction::WriteSegments                                                             ▒
      - 59.37% nsPipeOutputStream::WriteSegments                                                                       ▒
         - 33.53% mozilla::net::nsHttpTransaction::WritePipeSegment                                                    ▒
            - 21.55% mozilla::net::TLSFilterTransaction::OnWriteSegment                                                ▒
               - 18.18% PSMRecv                                                                                        ▒
                  - 9.20% mozilla::psm::TransportSecurityInfo::GetErrorCode                                            ▒
                       3.93% __pthread_mutex_unlock_usercnt                                                            ▒
                       3.19% __pthread_mutex_lock                                                                      ▒
                  + 4.46% (anonymous namespace)::checkHandshake                                                        ▒
                  + 1.97% PR_SetError                                                                                  ▒
               + 1.42% PR_GetError                                                                                     ▒
              3.64% __pthread_mutex_unlock_usercnt                                                                     ▒
              3.51% __pthread_mutex_lock                                                                               ▒
              0.84% mozilla::TimeStamp::Now                                                                            ▒
           7.49% __pthread_mutex_lock                                                                                  ▒
           6.74% PR_ExitMonitor                                                                                        ▒
           3.39% __pthread_mutex_unlock_usercnt                                                                        ▒
           0.81% PR_EnterMonitor                                                                                       ▒
        4.19% __pthread_mutex_unlock_usercnt                                                                           ▒
        0.99% mozilla::TimeStamp::Now                                                                                  ▒
   + 5.21% start_thread                                                                                                ▒

Comment 1

[Dana Keeler (she/her) (use needinfo) [:keeler] (on leave)]

Does reverting https://hg.mozilla.org/mozilla-central/rev/7b439431eb95 fix it?

Comment 2

[Kershaw Chang [:kershaw]]

This could also be a duplicate of bug 1484947.

Comment 3

[Steve Fink [:sfink] [:s:]]

Yes, that bug matches my symptoms. (It has not come back since I disabled the NordVPN extension.)