futurshox

Thank you very much, Jimbo_head.

Jimbo_head, thanks for your reply. How do I see if a script is running, and how do I monitor server load? Does it require some kind of exec() command?

I am building an alarm system which reacts to data files being received via FTP at 2-minute intervals. An existing script runs in cron every 2 minutes which reads the data file and inserts the data into a database. My alarm system reads the database and examines the latest data against pre-set tolerance limits. If the data is outside tolerance then emails need to be sent to recipients whose addresses reside in a database. They are split into two groups. Each group can set their own tolerances, and each person may belong to one of three shifts so messages need to be filtered to the right people. There will be somewhere between 50-100 people. User settings also include time intervals. Repeated instances of out-of-tolerance data should result in repeated alarms at pre-set intervals (in minutes). Likewise, once data has been within tolerance for a separate pre-set time then the all-clear should be sent. Currently I have this running every 10 minutes and it is working OK. However I have been asked to make it run every 2 minutes so the latest data is always examined. I am concerned about putting load onto our (shared) server and therefore I have some questions: - How long does it take to send 100 emails? - What happens if the script takes longer than 2 minutes to run, does it start overlapping jobs in cron? - Should I split the alarm script so that the triggers are part of the incoming data script (which runs at 2-min intervals anyway) and keep the repeat alert/all clear stuff in a separate script that runs every 5 minutes instead? - Is it really bad to run a cron job every minute? I may be asked to do this in future; my gut feeling says "don't do it!" but am I being too paranoid? I'm just really worried that if a script runs away, the next one will bog down, then the next one and so on.... - Is it possible to tell when a script is running, or has stopped running, in PHP? Could I run a script that said "Only run this include() file if there are no other instances of this script running"? Any suggestions/insights would be very appreciated! Thank you!

Thanks, that helps.

Say you have a script which runs in cron to do a specific job, so it's not part of a web page. It has data going in and out, with a few database transactions on the way. It might have to do the same job with data coming from one to 60+ inputs at once, looping through each inputted data chunk in turn. Yeah, that's as open-ended as anything, I realise, but I'm just looking for a ballpark idea of how long such a script should take to run. 50ms? 500ms? Thanks!

You should have a look at GD fonts. Have a Google for GD font converter*, and check out http://us2.php.net/manual/en/function.imageloadfont.php. The idea is to use the fonts to write onto an image, and then output the image. Which may or may not be suitable for what you want to do. This may also be useful but I've not played with it yet: http://us2.php.net/manual/en/function.imagettftext.php * You'll see a lot of references to a converter by a chap named Phillip, but this seems to have gone.

OK, thank you for your advice. The code is this: <?php $dbname="name"; $connectdb = mysql_connect('localhost', 'user', 'pass') or die("Could not connect to database: " . mysql_error()); $db = mysql_select_db($dbname, $connectdb) or die ('Can\'t use database : ' . mysql_error()); // copy from currentdata into daydata, but we need to generate the indexkey for this table $insert="INSERT INTO daydata (stationid, datestamp, wspeed, wdir, wsector, tout, hout, indexkey) VALUES "; $values=''; $sql="SELECT * FROM currentdata"; $result=mysql_query($sql); while ($myrow=mysql_fetch_array($result,MYSQL_ASSOC)) { $STATION=$myrow['stationid']; $datestamp=$myrow['datestamp']; $myrow['indexkey']=$datestamp.$STATION; $values.="('".implode("','",$myrow)."'),"; } if (substr($values,-1)==',') { $values=substr($values,0,-1); } // knock the last comma off $newsql=$insert.$values." on duplicate key update indexkey=VALUES(indexkey)"; // need to 'update if duplicate' due to different update intervals from each station $newresult=mysql_query($newsql); // delete data older than 24 hours $date1 = gmmktime(); $date2 = $date1-86400; // minus 1 day $date3 = date('Y-m-d H:i:s',$date2); $sql2 = "DELETE FROM daydata WHERE datestamp < '$date3'"; $result2 = mysql_query($sql2); // we want to group data by company so fetch the stations and order by CID $mainarray=array(); $sql4="select * from alarmsettings order by CID, STATION"; $result4=mysql_query($sql4); while ($myrow=mysql_fetch_array($result4,MYSQL_ASSOC)) { $CID=$myrow['CID']; $STATION=$myrow['STATION']; $mainarray[$CID][$STATION]['CID']=$CID; $mainarray[$CID][$STATION]['stationid']=$STATION; $mainarray[$CID][$STATION]['alertfreqmins']=$myrow['alertfreqmins']; $mainarray[$CID][$STATION]['allclearmins']=$myrow['allclearmins']; $mainarray[$CID][$STATION]['deadhours']=$myrow['deadhours']; $mainarray[$CID][$STATION]['alertstate']=$myrow['alertstate']; $mainarray[$CID][$STATION]['firsttrigger']=$myrow['firsttrigger']; $mainarray[$CID][$STATION]['lasttrigger']=$myrow['lasttrigger']; $mainarray[$CID][$STATION]['lastsent']=$myrow['lastsent']; $mainarray[$CID][$STATION]['allclear']=$myrow['allclear']; $mainarray[$CID][$STATION]['windspeed']=$myrow['windspeed']; $mainarray[$CID][$STATION]['windsector']=$myrow['windsector']; $mainarray[$CID][$STATION]['temphigh']=$myrow['temphigh']; $mainarray[$CID][$STATION]['templow']=$myrow['templow']; $mainarray[$CID][$STATION]['humhigh']=$myrow['humhigh']; $mainarray[$CID][$STATION]['humlow']=$myrow['humlow']; } $utc_str = gmdate("Y-m-d H:i:s", time()); $utcH = gmdate("H", time()); $now = strtotime($utc_str); foreach ($mainarray as $CID=>$location) { // loop through companies $response=array(); $alert=array(); $allclear=array(); foreach ($location as $STATION=>$info) { // check trigger times against $now and $alertfreqmins. $alarm=0; $send_response=0; $dead_hours=0; // fetch latest data $sql5="select * from currentdata where stationid='$STATION' order by datestamp desc limit 1"; $result5=mysql_query($sql5); if (mysql_num_rows($result5)>0) { // if no result, there's nothing to compare with $myrow5=mysql_fetch_array($result5,MYSQL_ASSOC); // ALARM TRIGGERS // TEMP if (!empty($info['templow']) and $info['templow']>=$myrow5['tout']) { $alert[$STATION]['TempLo']=$myrow5['tout']; } if (!empty($info['temphigh']) and $info['temphigh']<=$myrow5['tout']) { $alert[$STATION]['TempHi']=$myrow5['tout']; } // HUMIDITY if (!empty($info['humlow']) and $info['humlow']>=$myrow5['hout']) { $alert[$STATION]['HumLo']=$myrow5['hout']; } if (!empty($info['humhigh']) and $info['humhigh']<=$myrow5['hout']) { $alert[$STATION]['HumHi']=$myrow5['hout']; } // WIND if (!empty($info['windspeed']) and $info['windspeed']<=$myrow5['wspeed'] ) { $alert[$STATION]['WSpeedHi']=round($myrow5['wspeed'],1); } $shortcompass = array('N','NE','E','SE','S','SW','W','NW'); $wsector_in = $shortcompass[round($myrow5['wdir'] / 45) % 8]; if (!empty($info['windsector']) and stripos($info['windsector'],$wsector_in)!==false ) { $alert[$STATION]['WSector']=$wsector_in." (".$myrow5['wsector'].")"; } // $now is UTC in seconds from above $first_trigger=strtotime($info['firsttrigger']); $last_trigger=strtotime($info['lasttrigger']); $last_sent=strtotime($info['lastsent']); // IF ANY ALERT HAS BEEN TRIGGERED if (count($alert[$STATION])>0) { $alertstate="alertstate='1', "; // DETERMINE WHETHER TO SEND ALARM MESSAGE OR NOT if ($now-$last_sent>=($info['alertfreqmins']*60)-300) { // if enough time has elapsed since the last alarm trigger (with 5-min fudge factor) $send_response=1; $new_last_sent="lastsent='$utc_str', "; } else { $new_last_sent=''; } if (stripos($info['deadhours'],$utcH)!==false) { // check for dead hours on this location $dead_hours=1; } // SET TIMESTAMPS if ($first_trigger<$now-(($info['alertfreqmins']*60) + ($info['allclearmins']*60)) ) { // resetting firsttrigger for new alarm event $sql6="update alarmsettings set $alertstate $new_last_sent firsttrigger='$utc_str', lasttrigger='$utc_str' where STATION='$STATION' "; $result6=mysql_query($sql6); } else { $sql6="update alarmsettings set $alertstate $new_last_sent lasttrigger='$utc_str' where STATION='$STATION' "; $result6=mysql_query($sql6); } // BUILD MESSAGE IF SENDABLE if ($send_response==1 and $dead_hours==0) { $string="$STATION: "; foreach ($alert[$STATION] as $key=>$value) { $string.="\n$key=$value "; } $response[$STATION]=$string."\n"; } } else { // NO ALERT TRIGGERED // if enough time has passed for the all-clear AND we are in an alert state, send an all-clear. if ($now>($last_trigger + ($info['allclearmins']*60)) and $info['alertstate']==1) { $allclear[$STATION]="$STATION all-clear\n"; $sql6="update alarmsettings set alertstate='0', allclear='$utc_str' where STATION='$STATION' "; $result6=mysql_query($sql6); } } // end if count($alert[$STATION])>0 } // end if mysql_num_rows($result5)>0 } // end foreach($location) if (count($response)>0) { send_response($CID,$response,$utc_str); } if (count($allclear)>0) { send_allclear($CID,$allclear,$utc_str); } } // end foreach($CID) function send_response($CID,$response,$utc_str) { $to = fetch_addresses($CID); // log messages sent in new table and build email message $values=''; $email=''; $where=''; foreach ($response as $STATION=>$msg) { $values.="('$utc_str','$STATION','$CID','$msg','alarm'),"; $email.=$msg; $where.=$STATION." "; } if (substr($values,-1)==',') { $values=substr($values,0,-1); } $sqlstart="insert into alarmlogger (alertdate,STATION,CID,alertmsg,alerttype) values "; $sql8=$sqlstart.$values; $result8=mysql_query($sql8); send_email("WX Alarm $where",$email,$to); } function send_allclear($CID,$allclear,$utc_str) { $to = fetch_addresses($CID); // log messages sent in new table and build email message $values=''; $email=''; $where=''; foreach ($allclear as $STATION=>$msg) { $values.="('$utc_str','$STATION','$CID','$msg','allclear'),"; $email.=$msg; $where.=$STATION." "; } if (substr($values,-1)==',') { $values=substr($values,0,-1); } $sqlstart="insert into alarmlogger (alertdate,STATION,CID,alertmsg,alerttype) values "; $sql8=$sqlstart.$values; $result8=mysql_query($sql8); send_email("WX All-Clear $where",$email,$to); } function fetch_addresses($CID) { $sql7="select * from alarmusers where CID='$CID' "; $result7=mysql_query($sql7); $email_to=array(); while ($myrow7=mysql_fetch_array($result7,MYSQL_ASSOC)) { $email_to[]=$myrow7['email']; } $to=implode(",",$email_to); return($to); } function send_email($subject,$message,$to) { $from="me@here.net"; $fromname="Alerter"; $fromaddress="me@here.net"; $reply="me@here.net"; $eol="\r\n"; # Common Headers $headers = "From: ".$fromname."<".$fromaddress.">".$eol; $headers .= "Reply-To: ".$fromname."<".$fromaddress.">".$eol; $headers .= "Return-Path: ".$fromname."<".$fromaddress.">".$eol; // these two to set reply address $headers .= "Message-ID: <".time()."-".$fromaddress.">".$eol; $headers .= "X-Mailer: PHP v".phpversion().$eol; // These two to help avoid spam-filters mail($to,$subject,$message,$headers); } ?> When writing a script like this, how many SQL queries are too many? I have been trying to reduce the number of them but is that really the problem? Example of the alarmsettings table: STATION CID alertfreqmins allclearmins deadhours alertstate firsttrigger lasttrigger lastsent allclear windspeed windsector temphigh templow humhigh humlow XYZ 8 60 20 NULL 1 2008-10-23 13:20:02 2008-10-23 14:20:03 2008-10-23 13:40:02 2008-10-23 07:50:03 5 S 15 0 90 0 Thank you, Jo

I am sorry for the misunderstanding, this is a simplification of the script in an attempt to show only the logic of what it's doing.

Hello, this is my first post here. I am trying to make an alarm system. I have got it mostly built and it works, but my ISP is complaining that it chews up a lot of CPU resources. And this is just in testing, with only a small set of data (nine records). They are telling me that nested loops are the culprit. They're probably right, but I just don't know what else to use. OOP is a mystery to me. I will describe below what the script is doing. It is meant to run via cron every 10 minutes. I am trying not to process data for which there is no need, so the script starts processing by addressing only the stations for which settings have been made. Then it will filter them by company, so messages for companies with mutiple locations get sent as one, not many. Please can anyone tell me if there is a better way of doing this kind of thing? (This is PHP, there must be!) What should I be learning to write this stuff more efficiently? Thank you, Jo Apache version 1.3.41 (Unix) PHP version 5.2.3 MySQL version 5.0.45-community (first, other scripts put data into currentdata table) // SQL: copy incoming current data from currentdata into daydata // SQL: delete data older than 24 hours from daydata // SQL: fetch locations and settings from alarmsettings table and order by company foreach (company) { foreach (location) { // SQL: fetch latest data from daydata // compare current data against alarm settings if (alarm_triggered) { // if enough time has elapsed since the last alarm trigger, set 'send_response' flag // SQL: update timestamps/alertstate in daydata according to when the last trigger occurred } else { // if no alarm // if enough time has passed for the all-clear AND we are in an alert state, set all-clear. // SQL: update daydata with all-clear timestamp } } // end foreach(location) if (company_alarm>0) { send_response() } if (company_allclear>0) { send_allclear() } } // end foreach(company) function send_response() { $to = fetch_addresses(); // SQL: insert log messages sent in alarmlog table // send_email() // (later: send SMS) } function send_allclear() { $to = fetch_addresses(); // SQL: insert log messages sent in alarmlog table // send_email() // (later: send SMS) } function fetch_addresses() { // SQL: select email from alarmusers where company='company' // return addresses } function send_email() { mail($to,$subject,$message,$headers); }