In this post, I’d like to show some examples of how to extend Apache HTTPD logging so that there is additional information available for debugging requests that fail. Introduction There are two log files that Apache HTTPD writes to by default. These are the access_log and error_log. The access_log records…

Event MPM In this MPM, the tasks involved in handling a HTTP request are split between a listener thread and multiple worker threads. As long as a TCP connection is open, it transitions via some of these connection states - CONN_STATE_CHECK_REQUEST_LINE_READABLE, CONN_STATE_READ_REQUEST_LINE, CONN_STATE_HANDLER, CONN_STATE_WRITE_COMPLETION, CONN_STATE_SUSPENDED, CONN_STATE_LINGER, CONN_STATE_LINGER_NORMAL,

Why was the WebSocket protocol developed ? The HTTP/1 communication model involves a client requesting a server for data and the server responding with that data. This approach works well when the client knows when to send the HTTP request asking for the data. …

A listening socket is created when the following system calls are executed - socket(int domain, int type, int protocol); int bind(int sockfd, const struct sockaddr *addr, socklen_t addrlen); int listen(int sockfd, int backlog); When listen() system call is executed it converts the socket into a passive socket that waits for…

Improving Apache HTTP Server’s performance using ListenCoresBucketsRatio directive Apache HTTPD provides a directive called ListenCoresBucketsRatio. Documentation of this directive can be found at https://httpd.apache.org/docs/2.4/mod/mpm_common.html#listencoresbucketsratio The description of this directive as stated here reads — “A ratio between the number of (online) CPU cores and the number of listeners’ buckets can…

When reading the strace output of a multithreaded process that also forks child processes, it sometimes becomes necessary to distinguish between thread creation and process creation. In this article, I would like to describe a simple way to do this to help debugging easier. While looking at the strace output…

Balur is located in the Mudigere taluk of Chikkamagaluru district, Karnataka. Balur estate is a coffee plantation of 400 acres that has been around since the 1840s. We visited this place in May of 2015 to experience the coffee plantation and the old bungalows in the estate. The trip to…

The temple towns of Belur and Halebeedu lie in Hassan district of Karnataka. We visited these temples a week ago on a day trip from Bangalore. A deviation after Hagare, Hassan took us through roads that meander through farmlands growing maize, paddy, coconut and arecanut. The lush green paddy fields…

My husband and I visited New Zealand in November of 2015. Here, I attempt to capture some of the memories of that trip. Waitomo is a region in the north island of New Zealand that contains limestone caves. We traveled to Waitomo from Auckland as part of the GreatSights tour…