From 11a28834fa7ecf74fd9ebcd2b793caba21246cf1 Mon Sep 17 00:00:00 2001
From: adoda <zj_zhangjie_zj@126.com>
Date: Fri, 1 Mar 2019 18:15:48 +0800
Subject: [PATCH] [tune] Reduce the times for flushing json object to file
 (#4198)

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## What do these changes do?

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When we write one result using JsonLogger, it will call 'flush' many times, which may cost a lot of time when writing  to a remote distributed filesystem.

## Related issue number
#4197
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---
 python/ray/tune/logger.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/python/ray/tune/logger.py b/python/ray/tune/logger.py
index 6a6f766e2..7f4bddac8 100644
--- a/python/ray/tune/logger.py
+++ b/python/ray/tune/logger.py
@@ -90,10 +90,10 @@ class JsonLogger(Logger):
     def on_result(self, result):
         json.dump(result, self, cls=_SafeFallbackEncoder)
         self.write("\n")
+        self.local_out.flush()
 
     def write(self, b):
         self.local_out.write(b)
-        self.local_out.flush()
 
     def flush(self):
         self.local_out.flush()