config_funs.txt

purgeScriptFun
--------------
<<"
fun (PartTables) ->
	MIN_FREE_MEM_PERCENT = 40,
	TABLE_EXPIRY_MARGIN_SEC = -200,
	CSV_SEP_PTRN = \"\\\",\\\"\",
	SortedPartTables =
	    lists:sort([{imem_meta:time_to_partition_expiry(T),
			 imem_meta:table_size(T),
			 lists:nth(3, imem_meta:parse_table_name(T)), T}
			|| T <- PartTables]),
	OsInfo = case os:type() of
		   {win32, _} ->
		       [H, C] = [[string:strip(R, both, $\")
				  || R
					 <- re:split(E, CSV_SEP_PTRN,
						     [{return, list}])]
				 || E
					<- re:split(os:cmd(\"systeminfo /FO CSV\"),
						    \"\r
\", [{return, list}]),
				    E /= []],
		       SysPropList = lists:zip(H, C),
		       [FreeMem, TotMem] =
			   [list_to_integer(re:replace(lists:nth(1,
								 re:split(R,
									  \" \")),
						       \"'\", \"\",
						       [global,
							{return, list}]))
			    || R
				   <- [proplists:get_value(\"Available Physical Memory\",
							   SysPropList),
				       proplists:get_value(\"Total Physical Memory\",
							   SysPropList)]],
		       {\"Windows\", FreeMem, TotMem};
		   {unix, _} ->
		       TotMem =
			   list_to_integer(string:strip(os:cmd(\"cat /proc/meminfo | awk '/MemTotal:/ \"
							       \"{print $2}'\"),
							both, $
)),
		       FreeMem =
			   list_to_integer(string:strip(os:cmd(\"cat /proc/meminfo | awk '/MemFree:/ \"
							       \"{print $2}'\"),
							both, $
)),
		       {\"Unix\", FreeMem, TotMem};
		   Unknown ->
		       {lists:flatten(io_lib:format(\"~p\", [Unknown])), 1, 1}
		 end,
	{Os, FreeMemory, TotalMemory} = OsInfo,
	MemFreePerCent = FreeMemory / TotalMemory * 100,
	io:format(user, \"[~s] Free ~p%~n\",
		  [Os, MemFreePerCent]),
	if MemFreePerCent < MIN_FREE_MEM_PERCENT ->
	       io:format(user,
			 \"[~s] Free mem ~p% required min ~p%~n Purging \"
			 \"in tables ~p~n\",
			 [Os, MemFreePerCent, MIN_FREE_MEM_PERCENT,
			  SortedPartTables]),
	       MapFun = fun ({TRemain, RCnt, Class, TName} = Itm, A) ->
				if TRemain < TABLE_EXPIRY_MARGIN_SEC ->
				       ClassCnt = length([Spt
							  || Spt
								 <- SortedPartTables,
							     element(3, Spt) =:=
							       Class]),
				       if ClassCnt > 1 -> [Itm | A];
					  true -> A
				       end;
				   true -> A
				end
			end,
	       DelCandidates = lists:foldl(MapFun, [],
					   SortedPartTables),
	       if DelCandidates =:= [] ->
		      _TruncCandidates = lists:sort(fun ({_, R1, _, _},
							 {_, R2, _, _}) ->
							    if R1 > R2 -> true;
							       true -> false
							    end
						    end,
						    SortedPartTables),
		      [{_, _, _, T} | _] = _TruncCandidates,
		      imem_meta:truncate_table(T),
		      io:format(user, \"[~s] Truncated table ~p~n\", [Os, T]);
		  true ->
		      [{_, _, _, T} | _] = DelCandidates,
		      imem_meta:drop_table(T),
		      io:format(user, \"[~s] Deleted table ~p~n\", [Os, T])
	       end;
	   true -> ok
	end
end
">>