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Questions tagged [tuning]

53 questions
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Apache performance issue, after "1000 total children" Apache no longer responds to HTTP requests. Not MaxClients issue?

Hoping someone can point me in the right direction as I've spent the last week trying to figure out where the "issue" is but haven't been able to, tried posting to the Apache users mailing lists but wanted to bounce it off here as well. Running…
Jerome
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Exhausting Linux machine TCP socket limit (~70k)?

I am the founder of torservers.net, a non-profit that runs Tor exit nodes. We have a number of machines on Gbit connectivity and multiple IPs, and we seem to be hitting a limit of open TCP sockets across all those machines. We're hovering around…
mo.
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Assigning Processes to CPU Cores

I have access to a CentOS 6 web server (a PHP/MySQL forum) running Apache 2.2.15 and MySQL 5.1.52. This box has dual oct-core Xeons. What I find looking over the CPU graphs is that the first two cores (0 and 1) hit 90% usage whilst the other…
jwbensley
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Behaviour of solaris tcp stack with relatively high RTT and bursty traffic

I have an application that is distributing data from New York to Tokyo over TCP running Solaris 10. Mean throughput is < 1Mbps, peak throughput can reach 20-30Mbps for seconds at a time though typical spikes are more like 10Mbps. Individual message…
Matt
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NGINX + PHP-FPM + MYSQL - High CPU, Low RAM

All of a sudden our server started to act really weird, extremely high CPU usage and low RAM usage. I've never seen this before and I'm not sure what to do. I feel like if I could get the system to start using more available RAM the CPU usage would…
Lew Ayotte
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How can I see if apache is overloaded and dropping or not accepting connections?

Basically I just want to see if apache is handling a current level of high traffic or if I need to tune it to handle more connections. (I have found plenty of information on the actual tuning, so no help needed there) I know it has been dropping or…
cat pants
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MySQL com_select?

I'm looking to tune my query cache a bit. According to 7.6.3.4. Query Cache Status and Maintenance in the manual: The Com_select value is given by this formula: Qcache_inserts + Qcache_not_cached + queries with errors found during the…
symcbean
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Apache tuning with very high-load LAMP server

I have a LAMP server that can be serving ~400 requests per second at times, the server configuration is: CPU: Intel Quad Core Xeon X3430 (4 x 2.40 GHz, 8MB Cache) RAM: 16 GB REG ECC DDR3 HD: 500 GB Enterprise Grade SATA II OS: CentOS 64 Bit (Latest…
Roy
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Filesystem/Options for intensive random I/O

I'm planning to (privately) deploy a server that will be hammered with random I/Os in files ranging from 100MB to 50GB. The requests will range from 128 KB to 4MB. The profile will be 50:50 concerning read and write with a tendency of a little more…
leto
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find out NUMA locality of process RAM

I am doing an application benchmark with multiple instances of the same application. I found out that pinning their processes (with sched_setaffinity under Linux, with TaskManager under Windows) to specific CPUs increases performance. So I would…
Thorsten Staerk
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Postfix seems too aggressive while sending newsletters

I'm having a problem sending newsletters to certain domains/servers, like yahoo or minor network providers. It's like I'm spamming their servers with connections and they tell me to stop after a short while. I do get a bunch of emails through, but…
SteffenNielsen
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freebsd 7.2 kern.threads.max_threads_per_proc doesn't change after reboot

I have some multithread apps on my server machine based on FreeBSD 7.2, so because of this I need to increase kern.threads.max_threads_per_proc to 4000 (default value is 1500). I changed it using "sysctl kern.threads.max_threads_per_proc=4096" and…
Valeriy Maslov
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Postfix tuning for high amount

I have do some benchmarks with postfix, where we send out 6 KB HTML Mails. We followed all tuning instructions published by Postfix and used Ramdisk for the queue. We were not able to send above 50 Mails / sec out. Does anyone have some input on how…
Nenad
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MySQL query times for tuning are different every time

I am tuning SQL query time for my slow query but every time I get different times so I can't evaluate my optimize solution. For example, I run query select * from abc where abc.status in (x,y,z) and abc.scale>123; three times, and I get result time…
Yadun
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RHEL - tcp_delack_min sysctl parameter missing on realtime kernels

I'm looking to modify the tcp_delack_min sysctl tunable on several RHEL/CentOS systems. It should be located at /proc/sys/net/ipv4/tcp_delack_min. I'm finding that it is missing in recent kernels. While the parameter is available on 2.6.24.7-161, I…
ewwhite
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