journald: Increase stdout buffer size sooner, when almost full

If the previous received buffer length is almost equal to the allocated
buffer size, before this change the next read can only receive a couple
of bytes (in the worst case only 1 byte), which is not efficient.

(cherry picked from commit 034e9719ac1ba88a36b05da38c7aa98761d42c77)

diff --git a/src/journal/journald-stream.c b/src/journal/journald-stream.c
index ec6dad62e83942d592c53c6e572b35cc3478007d..ad90062176846e7f7a07bc64df067d77b3ec97d8 100644 (file)
--- a/src/journal/journald-stream.c
+++ b/src/journal/journald-stream.c
@@ -512,8 +512,8 @@ static int stdout_stream_process(sd_event_source *es, int fd, uint32_t revents,
                 goto terminate;
         }
 
-        /* If the buffer is full already (discounting the extra NUL we need), add room for another 1K */
-        if (s->length + 1 >= s->allocated) {
+        /* If the buffer is almost full, add room for another 1K */
+        if (s->length + 512 >= s->allocated) {
                 if (!GREEDY_REALLOC(s->buffer, s->allocated, s->length + 1 + 1024)) {
                         log_oom();
                         goto terminate;