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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoPlainText>Hi All,<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I have a question on the setting "vm_memory_high_watermark" of RabbitMQ.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Be default, "vm_memory_high_watermark" is set to 800 MB.<o:p></o:p></p><p class=MsoPlainText>Based on the document, this means the fraction is 0.4.<o:p></o:p></p><p class=MsoPlainText>My system is Windows 2008 Server 64-bit. It has 24 GB ram installed.<o:p></o:p></p><p class=MsoPlainText>When I ran "rabbitmqctl status", I got a different fraction for "vm_memory_high_watermark".<o:p></o:p></p><p class=MsoPlainText>It is much smaller than 0.4, and it seems equal to 800 MB / 24 GB. <o:p></o:p></p><p class=MsoPlainText>However when I tried to use "rabbitmqctl set_vm_memory_high_watermark", I have to use 0.4 in order to get 800 MB VM.<o:p></o:p></p><p class=MsoPlainText>This is inconsistent.<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>I notice that the erl.exe has /LARGEADDRESSAWARE flag ON. <o:p></o:p></p><p class=MsoPlainText>This means the Erlang VM can use up to 4 GB ram instead of 2 GB on a 64-bit Windows.<o:p></o:p></p><p class=MsoPlainText>It is safe to raise vm_memory_high_watermark to 1.6 GB in this case?<o:p></o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText><o:p> </o:p></p><p class=MsoPlainText>Thanks,<o:p></o:p></p><p class=MsoPlainText>--Bin Chen<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>