Description of problem: On a busy system, loading some metrics in Grafana (like hotproc.psinfo.rss in our case) errors out with: Jun 20 08:26:22 pcp.example.com grafana-server[2312019]: t=2023-06-20T08:26:22+0000 lvl=eror msg="Received HTTP Error Response" logger=plugins.backend pluginId=pcp-redis-datasource code=414.000 data="<html>\r\n<head><title>414 URI Too Long</title></head>\r\n<body>\r\n<h1>414 URI Too Long</h1>\r\n<p><b>unknown servlet</b>: request URL too long</p><hr>\r\n<p><small><i>pmproxy/5.3.7</i></small></p>\r\n</body>\r\n</html>\r\n" url="http://pcp.example.com:44322/series/labels?series=a3d8ad83571e11cfe488a77ab15e2262a431139c%2Cb7fd03bc96068df375e6861ee76070697b0411b0%2Ccbb004475b7b82614b2bb140a68e228200cbdc76%2C6f8fdf502cda372806448c41e40e0404c8b343fa%2C62860603d3f9c932f2703817ca21c2bd95a9cb3d%2Cecd69bdd7fa323e2ba22f675f1a50347cb557703%2C7f84e0f0a1a25eabccde2d82e315cd721ab7ae22%2C4feaff2c7ddd3486087254a92640eec2012afed2%2Cd5a51d8ced66aae90b3a65a9e80ab0aaa4d92… Version-Release number of selected component (if applicable): grafana-pcp-3.2.0-3.el8.x86_64 How reproducible: 100% Steps to Reproduce: 1. have many series 2. load them in grafana Actual results: data can't be loaded Expected results: data is loaded Additional info: This has been fixed upstream in https://github.com/performancecopilot/grafana-pcp/pull/116 which is available since grafana-pcp 4.0, however it requires a change to pcp itself (https://github.com/performancecopilot/pcp/pull/1555) which is only available in PCP 6.0+
Or should this BZ be actually against pcp itself, as grafana-pcp will get an update via BZ#2193270, but that won't help before PCP is not also updated?
Thanks for the report and excellent self-diagnosis Evgeni! You're spot on, I think, in that this is already fixed. The PCP issue you mentioned has been back-ported to RHEL 8.9 - I'll assign this to Stan for double-checking though.
I didn't see the patch in pcp-5.3.7-17 (as currently in CentOS Stream 8), but I didn't look *too* closely.
You're right - I thought it was in the pmproxy-rollup-fixes patch but it's not. I'll update that one with the next rebuild, thanks.