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| -rwxr-xr-x | .times | 10 | ||||
| -rw-r--r-- | served/styles/about.css | 16 | ||||
| -rw-r--r-- | served/words/statistic-gifs.html | 197 | ||||
| -rwxr-xr-x | served/words/words.css | 6 | ||||
| -rwxr-xr-x | served/words/words.html | 1 |
5 files changed, 27 insertions, 203 deletions
diff --git a/.times b/.times index 4351af0..5848542 100755 --- a/.times +++ b/.times @@ -1,7 +1,7 @@ ,1722699430,1739445155,1739445155 .DS_Store,1716265453,1739645865,1739646135 .times-ignore,1708577778,1708577778,1724111977 -.times,1714751011,1740909668,1740909660 +.times,1714751011,1740910399,1740910382 readme.md,1739445155,1739445155,1739445155 .gitignore,1739445155,1739445155,1739445157 updateTimes.sh,1708577778,1708577778,1740776196 @@ -31,11 +31,11 @@ served/words,1722699427,1740909658,1740909660 served/words/debugging-my-sql-query.html,1739445155,1739445155,1739445200 served/words/a-really-long-week.html,1731536606,1734517744,1734517744 served/words/.DS_Store,1731546328,1739645858,1739646135 -served/words/words.html,1739445155,1739445155,1739445156 +served/words/words.html,1739445155,1740909702,1740909869 served/words/akkoma-postgres-migration.html,1712999241,1712999241,1724111977 -served/words/statistics-on-linux.html,1740534158,1740909628,1740909645 +served/words/statistics-on-linux.html,1740534158,1740909628,1740909668 served/words/writing.css,1739445155,1740907336,1740909645 -served/words/words.css,1739445155,1739445155,1739445156 +served/words/words.css,1739445155,1740909784,1740909869 served/words/seeding-rng-physically.html,1739445155,1739445155,1739445156 served/words/images,1731545028,1735837530,1735837532 served/words/images/.DS_Store,1731546575,1733259152,1733572182 @@ -92,7 +92,7 @@ served/styles/Recursive.woff2,1656619120,1656619120,1733663978 served/styles/Atkinson-Hyperlegible-Bold-102a.woff2,1589485906,1589485906,1733665201 served/styles/post.css,1739445155,1739445155,1739445156 served/styles/common.css,1739445155,1740826395,1740909645 -served/styles/about.css,1740573416,1740573835,1740573863 +served/styles/about.css,1740573416,1740573835,1740909869 served/styles/writing.css,1724117827,1731504611,1733662439 served/styles/Atkinson-Hyperlegible-Italic-102a.woff2,1589485906,1589485906,1734781985 served/styles/statistics.css,1739700443,1740829249,1740829271 diff --git a/served/styles/about.css b/served/styles/about.css new file mode 100644 index 0000000..4290313 --- /dev/null +++ b/served/styles/about.css @@ -0,0 +1,16 @@ +#cont { + display: grid; + width: 30rem; + grid-template-columns: 5rem 1fr 5rem; + grid-template-rows: 5rem 1fr 5rem; +} + +img { + grid-column: 2; + grid-row: 2; +} + +#text { + grid-column: 1 / 4; + grid-row: 1 / 4; +} \ No newline at end of file diff --git a/served/words/statistic-gifs.html b/served/words/statistic-gifs.html deleted file mode 100644 index 583974b..0000000 --- a/served/words/statistic-gifs.html +++ /dev/null @@ -1,197 +0,0 @@ ---- -template=post -title=Statistics on Linux with /proc -style=/styles/post.css -style=writing.css - -published=2025-03-02 4:00am CST - -description=I want to tell you how my statistic gifs are made :) ---- - -<style> - .manlink { - margin-top: -1rem; - } -</style> - -I've been wanting to make a little page for the statistics of my -webserver <i>(the system not the program)</i>. When I started to -research the APIs that I'd need, just on a whim one day with no -intention to start, I got grabbed by it and knew I had to start. - -Check it out: <a href="/starlight.html">starlight.html</a> - -<h2>a <code>/proc</code> foreword</h2> -The <code>/proc</code> filesystem, on Linux, is a sort of window into -the kernel. It lets you view some pretty detailed information by simply -reading some files (thanks everything-is-a-file linux). - -There's a lot of information about it in the man pages. -They might all be in one big one at <code>man proc</code> but, -like how they are on my server, they could be broken into separate pages -for distinct sections. - -I have linked the relevant pages at the top of their section. It's a link -to man7.org, which seems to be <i>the</i> source for Linux Kernel man pages -on the internet. man7 is linked from kernel.org which lends it -credibility at least. - -<h2>Memory</h2> - -<p class="manlink"><a href="https://man7.org/linux/man-pages/man5/proc_meminfo.5.html">man7.org/proc_meminfo</a></p> - -This one isn't too hard. I open the file <code>/proc/meminfo</code> and -look for the lines starting with <code>MemTotal</code> and <code>MemAvailable</code> -which are the total memory and currently available memory, respectively. They -are very well named :). For usage, I just subtract available from total. - -<h2>Network</h2> - -<p class="manlink"><a href="https://man7.org/linux/man-pages/man5/proc_net.5.html">man7.org/proc_net</a></p> - -If you <code>cat /proc/net/dev</code> you can see some stats about -your networking interfaces. This is what I parse, with some pain. - -I read the bytes columns from the receive and transmit sections. -These are total counts of bytes received since boot, so you'll -have to take two samples and subtract to get the number of bytes -in some time-span. - -Looking at it in the terminal, you might assume that the separator -between the columns was a tab character. I sure did! It is not a tab, -but many spaces. - -Because of spaces-and-not-tabs -<i>(not the tabs vs. spaces debate of usual, but with similarities)</i>, it proved -to be a bit annoying to parse. It made me finally -pull in a regex crate because I didn't feel like dealing with it -at the time. Eventually™ I want to write a skip-arbitrarily-many-whitespace -iterator, but for now <code>regex-lite</code> lives in my <code>Cargo.toml</code>. - -<h2>CPU</h2> - -<p class="manlink"><a href="https://man7.org/linux/man-pages/man5/proc_stat.5.html">man7.org/proc_stat</a></p> - -<code>/proc/stat</code> is the least obvious of the triplet. It has more than -just the CPU's information, but the cpu is what we're after. You'll notice many -CPU lines probably! I'm using the one starting just "cpu" without a number -(cpu0, cpu1, etc.) because I only have the 1 core. If I had more than one core -it'd work similarly, the just-cpu line sums the other ones, but then it could -show >100% usage 'cause it's per-core usage just added together. - -First things uh, second? To summarize from the man page:<br /> -The units of these values are <i>ticks</i>. There are <code>USER_HZ</code> -ticks per second. On most platforms it's 100 but you can -check the value for your system with <code>sysconf(_SC_CLK_TCK)</code>. - -<details> - <summary style="font-style: italic;">small C program to check _SC_CLK_TCK :)</summary> - <pre><code>#include <stdio.h> -#include <unistd.h> -int main() { - printf("USER_HZ is %i", sysconf(_SC_CLK_TCK)); -}</code></pre> -</details> - -But what columns of data do we use? From <a href="https://stackoverflow.com/a/3017438">this stackoverflow answer</a> -it seems that summing the user, nice, and system columns get you the total ticks. -The user and system make sense to me, time spent in user and system mode, -but what on earth is nice? I sure hope it is. - -The Internet tells me to check <code>man nice</code> -(<a href="https://man7.org/linux/man-pages/man1/nice.1.html">man7.org/nice</a>). -That page says that the -nicness of a process can be adjusted to change how the kernel schedules -that process. Making it less nice (down to -20) increases it's priority, and -increasing it's niceness (up to 19) lowers it. I guess that makes sense. Lowering -the niceness makes the process greedier and in want of more attention -from the scheduler? I'm unsure how well that personification tracks to reality, but -it helped me think about it. - -The nice column, then, seems to be the time spent in processes that -would go in the user column, but they have a different priority and -I guess differentiating that is important. - -Oh, but there might be more columns we want! -There's <a href="https://stackoverflow.com/a/10794088">another S.O. answer</a> -that I found while writing this that says the sixth and seventh columns should used -as well. These are irq/softirq and are time spent servicing -interrupts. I think it makes sense we'd want that, too. - -So you have all these columns—user, nice, system, irq, -and softirq—that add together to give you the total number -of ticks spent Doing Things since boot, and you have the number -of ticks in a second. Can you see where I'm going with this? - -Yup, take two samples some time span apart, subtract the former -from the later, and then you have how much time the processor spent -Doing Things. You can use that and the number of ticks in your time -span to calculate utilization. Or you just have how much actual time -The Computer spent Doing Work which is also pretty neat. Maybe you -can pay it an hourly wage. Is that just AWS? - -Something to watch out for:<br /> -apparently the numbers in <code>/proc/stat</code> can overflow and -wrap back to zero. I don't know what size integers they are so I'm -unsure how real of a risk that is, but it seemed worth mentioning here. - -<h2>So you've parsed the stats, now to graphs!</h2> - -My main trouble here was selecting a range that makes sense for -the data it's representing. - -Again, memory was easy. There is a -total, normally-unchanging amount of RAM, so I just use that as -the max. Perhaps there's something to be said about zooming further -in to see the megabyte-by-megabyte variance, but I am much more -interested in a "how close am I to the ceiling" kind of graph. Like, -would I hit my head if I jumped? that kind of thing. - -The CPU graph, though, that's very variable and a bit spiky. -I don't <i>really</i> care what the max value was if it's a spike, -it can go off the top for all I care, what I want to see is the -typical usage. - -If I just ranged to the max then I'd have what I call The Linode -Problem. I call it that, rather predictably, because that's what -Linode's graphs do and it makes them kind of useless? Great, I love -to see that spike up to 100%, but that's <i>all</i> that I can see now. - -So instead of max-grabbing, I sort the data and take the value that's -<i>almost</i> max. My series are 256 samples long, so what this looked -like was taking the 240th value in the array, getting the closest-highest -percent, and using that as the top of the range. - -This <i>does</i> mean if it's <i>very</i> spiky, I get The Linode Problem -again, but in that case I'm kind of okay with it. I sample every minute, -so my 256 pixel long graphs are roughly 4 hours long. If it spikes more -than 16 times in that period, perhaps that's worth looking into. - -Okay, CPU done. Network time! It's the same, pretty much. Where there was -one line, there are now two. And lots more spikes! I combine the receive -and transmit series into one <code>vec</code>, sort it, and take the 32nd -highest value. - -I draw the area under the line, too, because it was nigh impossible to see -the line when it was so.. discontinuous? We get another problem with that, -though, where the second-drawn line-and-underfill will obscure the one -drawn first. So then, to not overdraw an entire measurement, I try to draw -the average-larger one first. Which is to say, I take the average of both -series separately and draw the one with the bigger average first. That way -the smaller one will hopefully nestle under the larger, like a baby bird -hiding from the rain under their parents wing. - -<hr class="asterism-dash" /> - -That's how the range selection works, anyway. - -The graphs themselves are drawn on 256x160 gif because i like gif, 256 is -a good number, and they seem to compress better than png in this use case. - -One day I'd love to try and generate alternative text to describe -the general look of the graph. "The memory usage is steady at 300MB", -or something like "The network usage is variable, but averages 15.4kbps". - -That's it!<br /> -bye :) \ No newline at end of file diff --git a/served/words/words.css b/served/words/words.css index ffc899a..0bc724d 100755 --- a/served/words/words.css +++ b/served/words/words.css @@ -13,6 +13,10 @@ div { #written { grid-row: 1; grid-column: 1 / 2; + + display: flex; + flex-direction: column; + row-gap: 1rem; } #what-weeknotes { @@ -39,7 +43,7 @@ div { } h2 { - margin: 0 0 1rem 0; + margin: 0; } #weeknotes { diff --git a/served/words/words.html b/served/words/words.html index 9c43d6d..b3f0792 100755 --- a/served/words/words.html +++ b/served/words/words.html @@ -35,6 +35,7 @@ The writing is part of the website <a href="/atom.xml">Atom Feed</a>. <section id="written"> <h2>technical writings;<br>project updates</h2> + <a href="statistics-on-linux.html">Statistics on Linux with /proc</a> <!--<a href="akkoma-postgres-migration.html">Akkoma Postgres Migration</a>--> <a href="debugging-my-sql-query.html">Debugging My SQL Query</a> </section> |