From c87355bc80da9e2cba7f7723d7c6568dfa56f1a1 Mon Sep 17 00:00:00 2001 From: Vito Caputo Date: Fri, 8 Jan 2016 12:11:44 -0800 Subject: [PATCH] journal: normalize priority of logging sources The stream event source has a priority of SD_EVENT_PRIORITY_NORMAL+5, and stdout source +10, but the native and syslog event sources are left at the default of 0. As a result, any heavy native or syslog logger can cause starvation of the other loggers. This is trivially demonstrated by running: dd if=/dev/urandom bs=8k | od | systemd-cat & # native spammer systemd-run echo hello & # stream logger journalctl --follow --output=verbose --no-pager --identifier=echo & ... and wait, and wait, the "hello" never comes. Now kill %1, "hello" arrives finally. Cherry-picked from: 48cef29504b1ffc0df9929f2d8b2af2ad74d2b4a Related: #1318994 --- src/journal/journald-native.c | 4 ++++ src/journal/journald-stream.c | 2 +- src/journal/journald-syslog.c | 4 ++++ 3 files changed, 9 insertions(+), 1 deletion(-) diff --git a/src/journal/journald-native.c b/src/journal/journald-native.c index 851625de0..2c9cf6e7a 100644 --- a/src/journal/journald-native.c +++ b/src/journal/journald-native.c @@ -457,5 +457,9 @@ int server_open_native_socket(Server*s) { if (r < 0) return log_error_errno(r, "Failed to add native server fd to event loop: %m"); + r = sd_event_source_set_priority(s->native_event_source, SD_EVENT_PRIORITY_NORMAL+5); + if (r < 0) + return log_error_errno(r, "Failed to adjust native event source priority: %m"); + return 0; } diff --git a/src/journal/journald-stream.c b/src/journal/journald-stream.c index 15a554c34..b8607144b 100644 --- a/src/journal/journald-stream.c +++ b/src/journal/journald-stream.c @@ -448,7 +448,7 @@ int server_open_stdout_socket(Server *s) { if (r < 0) return log_error_errno(r, "Failed to add stdout server fd to event source: %m"); - r = sd_event_source_set_priority(s->stdout_event_source, SD_EVENT_PRIORITY_NORMAL+10); + r = sd_event_source_set_priority(s->stdout_event_source, SD_EVENT_PRIORITY_NORMAL+5); if (r < 0) return log_error_errno(r, "Failed to adjust priority of stdout server event source: %m"); diff --git a/src/journal/journald-syslog.c b/src/journal/journald-syslog.c index 4e118aabc..8602b4a95 100644 --- a/src/journal/journald-syslog.c +++ b/src/journal/journald-syslog.c @@ -421,6 +421,10 @@ int server_open_syslog_socket(Server *s) { if (r < 0) return log_error_errno(r, "Failed to add syslog server fd to event loop: %m"); + r = sd_event_source_set_priority(s->syslog_event_source, SD_EVENT_PRIORITY_NORMAL+5); + if (r < 0) + return log_error_errno(r, "Failed to adjust syslog event source priority: %m"); + return 0; }