From 1db9e7a8c7743d1794d85d1e35c292daa78d5c6e Mon Sep 17 00:00:00 2001
From: Tsubasa Nomura <tsubasa@nomupro.com>
Date: Fri, 4 Jun 2021 14:58:24 +0000
Subject: [PATCH]  Mem_Buf_limit  is configurable via ConfigMap

---
 .../installer/scripts/td-agent-bit-conf-customizer.rb  |  6 ++++++
 build/linux/installer/conf/td-agent-bit.conf           |  2 +-
 .../linux/installer/scripts/tomlparser-agent-config.rb | 10 ++++++++++
 3 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/build/common/installer/scripts/td-agent-bit-conf-customizer.rb b/build/common/installer/scripts/td-agent-bit-conf-customizer.rb
index ea1536866..82c6c1d17 100644
--- a/build/common/installer/scripts/td-agent-bit-conf-customizer.rb
+++ b/build/common/installer/scripts/td-agent-bit-conf-customizer.rb
@@ -6,6 +6,7 @@
 @default_service_interval = "1"
 @default_buffer_chunk_size = "1"
 @default_buffer_max_size = "1"
+@default_mem_buf_limit = "10"
 
 def is_number?(value)
   true if Integer(value) rescue false
@@ -19,6 +20,7 @@ def substituteFluentBitPlaceHolders
     interval = ENV["FBIT_SERVICE_FLUSH_INTERVAL"]
     bufferChunkSize = ENV["FBIT_TAIL_BUFFER_CHUNK_SIZE"]
     bufferMaxSize = ENV["FBIT_TAIL_BUFFER_MAX_SIZE"]
+    memBufLimit = ENV["FBIT_TAIL_MEM_BUF_LIMIT"]
 
     serviceInterval = (!interval.nil? && is_number?(interval) && interval.to_i > 0 ) ? interval : @default_service_interval
     serviceIntervalSetting = "Flush         " + serviceInterval
@@ -32,8 +34,12 @@ def substituteFluentBitPlaceHolders
       tailBufferMaxSize = tailBufferChunkSize
     end
 
+    tailMemBufLimit = (!memBufLimit.nil? && is_number?(memBufLimit) && memBufLimit.to_i > 10) ? memBufLimit : @default_mem_buf_limit
+    tailMemBufLimitSetting = "Mem_Buf_Limit " + tailMemBufLimit + "m"
+
     text = File.read(@td_agent_bit_conf_path)
     new_contents = text.gsub("${SERVICE_FLUSH_INTERVAL}", serviceIntervalSetting)
+    new_contents = new_contents.gsub("${TAIL_MEM_BUF_LIMIT}", tailMemBufLimitSetting)
     if !tailBufferChunkSize.nil?
       new_contents = new_contents.gsub("${TAIL_BUFFER_CHUNK_SIZE}", "Buffer_Chunk_Size " + tailBufferChunkSize + "m")
     else
diff --git a/build/linux/installer/conf/td-agent-bit.conf b/build/linux/installer/conf/td-agent-bit.conf
index 045aefcaf..beba6a3ca 100644
--- a/build/linux/installer/conf/td-agent-bit.conf
+++ b/build/linux/installer/conf/td-agent-bit.conf
@@ -19,7 +19,7 @@
     DB /var/log/omsagent-fblogs.db
     DB.Sync Off
     Parser docker
-    Mem_Buf_Limit 10m
+    ${TAIL_MEM_BUF_LIMIT}
     ${TAIL_BUFFER_CHUNK_SIZE}
     ${TAIL_BUFFER_MAX_SIZE}
     Rotate_Wait 20
diff --git a/build/linux/installer/scripts/tomlparser-agent-config.rb b/build/linux/installer/scripts/tomlparser-agent-config.rb
index e587909e5..4daaf6a0c 100644
--- a/build/linux/installer/scripts/tomlparser-agent-config.rb
+++ b/build/linux/installer/scripts/tomlparser-agent-config.rb
@@ -59,6 +59,7 @@
 @fbitFlushIntervalSecs = 0
 @fbitTailBufferChunkSizeMBs = 0
 @fbitTailBufferMaxSizeMBs = 0
+@fbitTailMemBufLimitMBs = 0
 
 
 def is_number?(value)
@@ -168,6 +169,12 @@ def populateSettingValuesFromConfigMap(parsedConfig)
           @fbitTailBufferMaxSizeMBs = @fbitTailBufferChunkSizeMBs
           puts "config::warn: since tail_buf_maxsize_megabytes not provided hence using tail_buf_maxsize_megabytes=#{@fbitTailBufferMaxSizeMBs} which is same as the value of tail_buf_chunksize_megabytes"
         end 
+
+        fbitTailMemBufLimitMBs = fbit_config[:tail_mem_buf_limit_megabytes]
+        if !fbitTailMemBufLimitMBs.nil? && is_number?(fbitTailMemBufLimitMBs) && fbitTailMemBufLimitMBs.to_i > 0
+          @fbitTailMemBufLimitMBs = fbitTailMemBufLimitMBs.to_i
+          puts "Using config map value: tail_mem_buf_limit_megabytes  = #{@fbitTailMemBufLimitMBs}"
+        end
       end
     end
   rescue => errorStr
@@ -212,6 +219,9 @@ def populateSettingValuesFromConfigMap(parsedConfig)
   if @fbitTailBufferMaxSizeMBs > 0
     file.write("export FBIT_TAIL_BUFFER_MAX_SIZE=#{@fbitTailBufferMaxSizeMBs}\n")
   end 
+  if @fbitTailMemBufLimitMBs > 0
+    file.write("export FBIT_TAIL_MEM_BUF_LIMIT=#{@fbitTailMemBufLimitMBs}\n")
+  end 
   # Close file after writing all environment variables
   file.close
 else