Status: Error: file /var/log/mysql/mysql. Status: Error: file /var/log/mysql/mysql.log does not exist Status: Error: file /var/log/mysql/mysql-slow.log does not exist Status: Error: file /var/log/mysql/mysql_error.log does not exist Status: Error: file /var/log/apache2/error.log does not exist Status: Error: file /var/log/apache2/access.log does not exist Unable to import module 'php': No module named php Metric Samples: Last Run: 17, Total: 1,426Ĭheck is not a jmx check, or unable to determine if it's so Instance ID: process:cron:9ed544564fb1c09b Metric Samples: Last Run: 31, Total: 2,573 Metric Samples: Last Run: 61, Total: 5,062 Metric Samples: Last Run: 61, Total: 5,123 Metric Samples: Last Run: 17, Total: 1,428 Metric Samples: Last Run: 26, Total: 2,166 Metric Samples: Last Run: 150, Total: 12,600 Gce: unable to retrieve hostname from GCE: Get : net/http: request canceled while waiting for connection (Client.Timeout exceeded while awaiting headers) Know what your server is purposed for and monitor responsibly.Config File: /etc/datadog-agent/datadog.yamlĪws: not retrieving hostname from AWS: the host is not an ECS instance, and other providers already retrieve non-default hostnamesĬonfiguration/environment: hostname is empty Note: If your load average is >1 for 24 hours a day then your host will never catch up (thank you captain obvious!).Ībove is an example of a server that has 4 cores, and is straddling the line of load, but because it’s just processing jobs that are not time sensitive, it’s ok.Ībove is an example of a server with 16 cores that is processing information that is time sensitive and is well within the load capacity of 16. If that host is in charge of chugging through a queue of work which you do not care when it finishes then you could probably tolerate a load average of >1 per core. If that host is in charge of delivering time sensitive information for public consumption, or even private consumption then you absolutely do not want your load average to be bigger than 1 per CPU core. It really depends on what that host is in charge of doing, and what the workload is. This is in my opinion the most important part of the question. Now to the second part of the question, “why do I care?”. So it’s possible to have a high load, and low CPU utilization. It’s like saying “there are 100 vehicles queued at the freeway on ramp.” It makes a big difference if those 100 vehicles are zippy motorbikes, or giant semi-trailers. Some of the jobs queued may have very high CPU requirements and take a long time to run, and others may schedule a request and then cede the CPU. In this scenario, anything less than 8 would put you under capacity and anything over 8 would put you in the queue.Īnother issue – load that is greater than your number of cores tells you that processes are queuing – but it tells you nothing about the type of work being queued. In modern production systems, monitoring systems track an ever-evolving system with changing software architecture, load characteristics, and performance. Duh, right? Here’s the point, if you have 8 cores then you can have an average CPU load of 8 and that would put you at capacity. That means that your core is at capacity (meaning there is one process running on the core, and nothing queued up waiting for it.) Think of 1 as being 100% capacity, so if you have 2 physical CPU’s and each of them have 4 cores then in grand total you have 8 cores. How many cores does each CPU have? Each core can handle a load average of 1. Good point! Who only has 1 CPU these days? Not me, that’s for sure! So what would be the load average number that would cause 2 CPU’s to be at capacity? It depends. But Cevin, I don’t have 1 CPU, I have 2 CPU’s. 5 that would mean you are at half capacity giving you room for more load. In this video you will get the basics down of what we do and some of our features. If you have a load average of 1 that would mean you are at capacity and anything more than that would start to queue. 96K views 6 years ago Datadog is a SaaS based monitoring platform with hundreds of integrations. Let’s say for example you have 1 CPU with 1 core. This can also be referred to as the run queue length. For the rest of you, let’s briefly discuss what exactly CPU load average really is.ĬPU load is the number of processes that are using, or want to use, CPU time, or queued up processes ready to use CPU. But what is this CPU load average metric?įor those of you who know all about CPU load average, now is when you might want to skip ahead to the portion of the blog where I give my philosophical opinion about if load average is useful. Who cares though? It’s obvious to me I want to know about CPU percent used because in my mind that tells me how much CPU resources are being utilized. I think everyone knows that if you run the top command you can get the 1 min 5 min and 15 min CPU load average for the box. In all reality I had a basic understanding of the concept of CPU load on a Linux server, but there were a few things I learned recently and I figured I’d share with the world.
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