Monitor

ahmedsmart4tech

Dears,
Could you please explain what is going on exactly on the lightstreamer monitor.
Regards,

Giuseppe Corti

Hi Ahmed,

The monitor states that at the moment the screenshot was taken:

the server allocate about 290 MBytes of total memory for the heap (of which about 5 are free).
14 sessions are established 12 in streaming mode, 2 in polling mode. Furthermore, since 14 connections are active this means 1 session : 1 connection.
365 Items are subscribed and the server in the last 2 second received an average of 39.46 upd/s from the adapters.
The server sends to the client an average of 114.39 upd/s and from the start 578 updates have been lost (the server had to discard them from the event buffer of a client).
No client messages activity.
The thread activity is quite calm, no queued tasks.

The server situation generally looks good and the only possible warnings seems to be:

the low amount of free heap, please could you confirm the settings for JVM memory option in the LS.bat launch script?
the messages lost, this may mean that one or more clients fail to processing all messages received from the server or the network bandwidth is not adequate to flow of data incoming.

Please note that more detailed info, from the same source of the monitor console, can be find in the LightstreamerMonitorText logger. A 'grep' of all lines of that logger can give a more complete picture of the performance of the server during the day.

You can find the complete description of the fields shown in the Monitor Console in the final paragraph (4.2.1) of the "General Concepts.pdf" document.
For a map of the fields used in the console HTML page, please refere to the source code, /src/index.html, of this GitHub project.

Regards,
Giuseppe

ahmedsmart4tech

Dear Giuseppe,
Thanks for your good and quick reply,
this is the LS.bat:
@echo off

if "%OS%" == "Windows_NT" setlocal

rem ====================================================================
rem === CHECK THIS OUT
rem ====================================================================
rem JAVA_HOME must point to your Java Development Kit installation
set JAVA_HOME=C:\Program Files\Java\jdk1.8.0_05\jre

rem =======================================================================
rem === CHECK THIS OUT
rem =======================================================================
rem JAVA_OPTS should contain any Java Virtual Machine options. Here are some tips:
rem 1) Always use the "-server" option.
rem 2) Give more RAM to the server process, especially with heavy traffic, by specifying a min and max "heap"
rem E.g.: If you have 4 GB and the box is dedicated to Lightstreamer, you might set 1 GB min heap and 3 GB max
rem heap with these options: "-Xms1G -Xmx3G"
rem 3) Choose a better "garbage collector" if you want to reduce latency. An option that often gives good results is:
rem "-XX:+UseConcMarkSweepGC". Only if you are using a very recent version of Java 7, you might prefer to try:
rem "-XX:+UseG1GC". Many other tuning options are available (please see Oracle docs).
set JAVA_OPTS=-server

rem --------------------------------------------------------------------

echo Java environment:
echo JAVA_HOME = %JAVA_HOME%
echo JAVA_OPTS = %JAVA_OPTS%
echo.

rem LS_HOME takes the current directory of LS.bat and goes up two dirs
set LS_HOME=%~dp0..\..\

echo Lightstreamer Server directory:
echo LS_HOME = %LS_HOME%
echo.

if ""%1"" == ""run"" goto doStart
if ""%1"" == ""silent"" goto doStart
if ""%1"" == ""background"" goto doStart
if ""%1"" == ""stop"" goto doStop
if ""%1"" == ""restart"" goto doStop

echo Usage: LS.bat ( command )
echo commands:
echo run Start Lightstreamer Server in the current window
echo background Start Lightstreamer Server in a separate window
echo stop Stop Lightstreamer Server
echo restart Stop Lightstreamer Server and start a new instance in a separate window
goto end

rem Main class

:doStart
echo Starting Lightstreamer Server...
echo Please check logs for detailed information.
set class=com.lightstreamer.LS
goto doLaunch

:doStop
echo Stopping Lightstreamer Server...
set class=com.lightstreamer.LS_Stop
goto doLaunch

:doLaunch

rem Configuration file
set args="%LS_HOME%\conf\lightstreamer_conf.xml"

rem Classpath
set cpath="%LS_HOME%\lib\lightstreamer.jar";"%LS_HOME%\lib\ls-adapter-interface.jar";"%LS_HOME%\lib\ls-monitor.jar";"%LS_HOME%\lib\*"

rem Launch command
set command="%JAVA_HOME%\bin\java.exe" %JAVA_OPTS% -cp %cpath% %class% %args%
set minimal_command="%JAVA_HOME%\bin\java.exe" -cp %cpath% %class% %args%

if ""%1"" == ""run"" goto doForeground
if ""%1"" == ""silent"" goto doSilent
if ""%1"" == ""background"" goto doBackground
if ""%1"" == ""stop"" goto doStop
if ""%1"" == ""restart"" goto doSubcall

:doSubcall
rem call command and wait
call %command%
%0 background
goto end

:doForeground
rem leave control to command
%command%
goto end

:doSilent
rem rerun after output redirection (for run as a service)
set output="%LS_HOME%\logs\LS.out"
%0 run 1>> %output% 2>&1
goto end

:doStop
rem leave control to command
%minimal_command%
goto end

:doBackground
rem call command in a separate window and leave
if not "%OS%" == "Windows_NT" goto noTitle
start "Lightstreamer Server" %command%
goto end
:noTitle
start %command%
goto end

:end

Giuseppe Corti

Hi Ahmed,

Thank you for provide us with the launch script in use.

I note that you have left the factory settings for the java options. I was afraid that the low value of free heap was due to a too low value set for -Xmx; but then was probably due to internal strategies of the JVM for memory allocation. The current Momitor shows values more appropriate.

Anyway, you could consider to set larger values for -Xms and -Xmx according to the amount of total physical memory available in your system. Please refer here for the Java default values.

Regards,
Giuseppe