Update to latest nixUnstable

Dependencies

• [2] BYVRA54Q Temporarily disable machines on any exception, not just connection failures
• [3] JPHDKOMJ hydra-queue-runner: Keep some notification statistics
• [4] IE2PRAQU hydra-queue-runner: Send build notifications
• [5] IKJBYIGY Update to reflect BinaryCacheStore changes
• [6] N4IROACV Move buildRemote() into State
• [7] FJCKDJKB Acquire the send lock only while actually sending
• [8] BRAESISH Warn if PostgreSQL appears stalled
• [9] SL3WSRAC hydra-queue-runner: Limit memory usage
• [10] V6H6BWMK Sync with Nix
• [11] N2NKSKHS Refactor local binary cache code into a subclass
• [12] B2L4T3X6 Sync with Nix
• [13] 4YCF3KBG Concurrent hydra-evaluator
• [14] UYDRSHYR Don't wait forever to acquire the send lock
• [15] YZAI5GQU Implement a database connection pool
• [16] HJOEIMLR Refactor
• [17] BG6PEOB2 Make the output size limit configurable
• [18] 73YR46NJ hydra-queue-runner: Write directly to a binary cache
• [19] MB3TISH2 Rate-limit the number of threads copying closures at the same time
• [20] 5AIYUMTB Basic remote building
• [21] 3YSJ3LYK Remove finally.hh
• [22] EYR3EW6J Keep stats for the Hydra auto scaler
• [23] GH4S4AWM Rename file
• [24] DIEY5USN Keep better bytesReceived/bytesSent stats
• [25] A4A5KO5Q Add error/warnings for deprecated store specification
• [26] A2GL5FOZ Moar stats
• [27] 24BMQDZA Start of single-process hydra-queue-runner
• [28] 7LB6QBXY Keep track of the number of build steps that are being built
• [29] GTUZLZRH Add an S3-backed binary cache store
• [30] FITVNQ2S Keep track of the time we spend copying to/from build machines
• [31] XLYHZUHT Cache .narinfo lookups
• [32] NAYQT2GT hydra-queue-runner: Use cmdBuildDerivation
• [33] MS676RZW Remove s3binarystore (moved to nix in d155d80)
• [34] ENXUSMSV Make concurrency more robust
• [35] MHVIT4JY Split hydra-queue-runner.cc more

Change contents

• file deletion: counter.hh (----------)
  [4.187]→[4.433:467](∅→∅),[4.467]→[4.234:234](∅→∅)
  − #pragma once

  −

  − #include <atomic>

  −

  − typedef std::atomic<unsigned long> counter;

  −

  − struct MaintainCount

  − {

  − counter & c;

  − MaintainCount(counter & c) : c(c) { c++; }

  − ~MaintainCount() { auto prev = c--; assert(prev); }

  − };

  − MaintainCount(counter & c, std::function<void(unsigned long)> warn) : c(c)

  − {

  − warn(++c);

  − }

  − #include <functional>
• replacement in src/hydra-queue-runner/build-remote.cc at line 234
  [2.2639]→[2.2639:2711](∅→∅)
  − auto mc1 = std::make_shared<MaintainCount>(nrStepsWaiting);
  [2.2639]

  [2.2787]
  + auto mc1 = std::make_shared<MaintainCount<counter>>(nrStepsWaiting);
• replacement in src/hydra-queue-runner/build-remote.cc at line 236
  [2.2812]→[2.2812:2861](∅→∅)
  − MaintainCount mc2(nrStepsCopyingTo);
  [2.2812]

  [2.2861]
  + MaintainCount<counter> mc2(nrStepsCopyingTo);
• replacement in src/hydra-queue-runner/build-remote.cc at line 279
  [2.3849]→[2.3849:3896](∅→∅)
  − MaintainCount mc(nrStepsBuilding);
  [2.3849]

  [2.3896]
  + MaintainCount<counter> mc(nrStepsBuilding);
• replacement in src/hydra-queue-runner/build-remote.cc at line 374
  [2.7058]→[2.7058:7108](∅→∅)
  − MaintainCount mc(nrStepsCopyingFrom);
  [2.7058]

  [4.4791]
  + MaintainCount<counter> mc(nrStepsCopyingFrom);
• replacement in src/hydra-queue-runner/hydra-queue-runner.cc at line 108
  [4.308]→[4.308:345](∅→∅)
  − MaintainCount State::startDbUpdate()
  [4.308]

  [4.345]
  + nix::MaintainCount<counter> State::startDbUpdate()
• replacement in src/hydra-queue-runner/hydra-queue-runner.cc at line 110
  [4.347]→[4.347:566](∅→∅)
  − return MaintainCount(nrActiveDbUpdates, [](unsigned long c) {

  − if (c > 6) {

  − printMsg(lvlError, format("warning: %d concurrent database updates; PostgreSQL may be stalled") % c);

  − }

  − });
  [4.347]

  [4.1621]
  + if (nrActiveDbUpdates > 6)

  + printError("warning: %d concurrent database updates; PostgreSQL may be stalled", nrActiveDbUpdates.load());

  + return MaintainCount<counter>(nrActiveDbUpdates);
• replacement in src/hydra-queue-runner/hydra-queue-runner.cc at line 486
  [3.1]→[3.1:58](∅→∅)
  − MaintainCount mc(nrNotificationsInProgress);
  [3.1]

  [4.1801]
  + MaintainCount<counter> mc(nrNotificationsInProgress);
• edit in src/hydra-queue-runner/state.hh at line 11
  [4.1277]→[4.1277:1299](∅→∅)
  − #include "counter.hh"
• edit in src/hydra-queue-runner/state.hh at line 24
  [4.1567]

  [4.1567]
  + typedef std::atomic<unsigned long> counter;
• edit in src/hydra-queue-runner/state.hh at line 26
  [4.1568]

  [4.1568]
  +
• replacement in src/hydra-queue-runner/state.hh at line 443
  [4.13176]→[4.911:946](∅→∅)
  − MaintainCount startDbUpdate();
  [4.13176]

  [4.13314]
  + nix::MaintainCount<counter> startDbUpdate();