<html><head></head><body><div style="color:#000; background-color:#fff; font-family:HelveticaNeue, Helvetica Neue, Helvetica, Arial, Lucida Grande, sans-serif;font-size:16px"><div id="yui_3_16_0_ym19_1_1483356359812_15679">Hello list,</div><div id="yui_3_16_0_ym19_1_1483356359812_15680"><br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">I have a nice distributed erlang application which has around 50 nodes (10 of them are c-nodes), which is running smoothly. I'm on 16B01 on redhat 6.3.</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">all of them share the same mnesia database - but only some of them read/write extensively to it. There is one table 'params' that everyone use to keep a stored set of parameters on one node (disc copies on that node, ram copies on the rest).</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">all is well, except...</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">I want to double the nodes and the lab testing does not get past 65-70 nodes.</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">Here are some questions:</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">* what tools do you use to find the specific problem (it could be the erlang cluster epmd n^2 messages, the shared mnesia cluster, the stupid param table)</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">* any nice quick fixes (running everything as hidden, break the cluster, delete the stupid table)</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">* long-run fixes: switch from mnesia to something else? hire good programmers?</div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr"><br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">Thanks a lot,<br></div><div id="yui_3_16_0_ym19_1_1483356359812_15680" dir="ltr">Dror</div></div></body></html>