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| bio | website | expletiveinserted.com |
|---|---|---|
| location | Seattle, WA | |
| age | ||
| visits | member for | 2 years, 11 months |
| seen | Apr 3 at 21:34 | |
| stats | profile views | 8 |
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Mar 29 |
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What might be causing this intermittent PHP stalling event? If only. And yes, I don't think xdebug on such an intermittent issue is practical in production. |
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Mar 29 |
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What might be causing this intermittent PHP stalling event? Yes. There are no errors in the logs (I'll make that more clear above). No complaints that anything is running out of memory (the PHP memory limit is currently 128MB). Could an OOM happen silently and stall execution? |
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Apr 26 |
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Should AWS CloudFront *increase* load time for infrequently accessed files? You are correct that the cache-control influences how long the content is kept at the edge. The TTL is a separate matter though. TTL controls the caching of the IP address assigned to the domain name. So regardless of whether the static file is cached at the edge or not, the first time a server sees the URL of the file it has to find the IP address of this domain. With 1-day TTL, it is likely that a nearby server has this info in its DNS cache. With a 5 minute TTL this is much less likely and a complete round trip to my origin server is required (not for the file, but to resolve the URL).. |
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Apr 19 |
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Should AWS CloudFront *increase* load time for infrequently accessed files? I have updated the question with another potential explanation for the perf issue I saw, which is that I had left the TTL setting at the low setting of 5 minutes, but when switching back to 12 hours I don't think I'm seeing these occasional perf issues as often. |
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Apr 14 |
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Should AWS CloudFront *increase* load time for infrequently accessed files? Very useful info. Thanks. |
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Mar 27 |
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Should AWS CloudFront *increase* load time for infrequently accessed files? Thanks again. That cache-control link isn't relevant to my situation because I'm using a custom origin server, not s3. But the principal applies and I do have far future expires headers set. BTW, Amazon's docs do say that content lives in the cache for 24 hours, but my experiments indicate something different. |
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Mar 27 |
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Should AWS CloudFront *increase* load time for infrequently accessed files? Thanks Jesse - very helpful. The point regarding scaling is well taken. And we have sufficient traffic for it to make a big difference. I would still love to know the caching policy though. I have found an enormous amount of info about HOW to set up the CDN and very little about its characteristics. I'm wondering, for example, whether I should exclude (from the CDN) old content that is accessed very infrequently. |
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May 26 |
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How can I tell which page is creating a high-CPU-load httpd process? Thanks Peter. On first glance The Grinder seems focused on Java, but I'll look into it. |
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May 25 |
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How can I tell which page is creating a high-CPU-load httpd process? No, no leap in time. Here is a pastie of part of the strace output where the transition seems to happen: pastie.org/976727. At the top it is in my site, and at the bottom it is heading into the python folders. |
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May 25 |
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How can I tell which page is creating a high-CPU-load httpd process? Wow. The strace output is fascinating. What an education. I can actually see where the system is looking first in the root folder for my "require"s because I didn't include "./" in the path. Some very strange output though. Some of the CPU-hungry processes seem to start out in my site and then go on a tangent into ""/usr/lib/python24...". I'm not using python anywhere. What could this be? |
