pgstat 1.0.0 is out!
Par Guillaume Lelarge le samedi, février 28 2015, 23:46 - PlanetPostgreSQL - Lien permanent
Since the last time I talked about it, I had quite a few feedbacks, bug issues, pull requests, and so on. Many issues were fixed, the last of it tonight.
I also added two new reports. I had the idea while working on my customers' clusters.
One of them had a lot of writes on their databases, and I wanted to know how much writes occured in the WAL files. vmstat would only tell me how much writes on all files, but I was only interested in WAL writes. So I added a new report that grabs the current XLOG position, and diff it with the previous XLOG position. It gives something like this with a pgbench test:
$ ./pgstat -s xlog -------- filename -------- -- location -- ---- bytes ---- 00000001000000000000003E 0/3EC49940 1053071680 00000001000000000000003E 0/3EC49940 0 00000001000000000000003E 0/3EC49940 0 00000001000000000000003E 0/3EC875F8 253112 00000001000000000000003E 0/3ED585C8 856016 00000001000000000000003E 0/3EE36C40 910968 00000001000000000000003E 0/3EEFCC58 811032 00000001000000000000003E 0/3EFAB9D0 716152 00000001000000000000003F 0/3F06A3C0 780784 00000001000000000000003F 0/3F0E79E0 513568 00000001000000000000003F 0/3F1354E0 318208 00000001000000000000003F 0/3F1F6218 789816 00000001000000000000003F 0/3F2BCE00 814056 00000001000000000000003F 0/3F323240 418880 00000001000000000000003F 0/3F323240 0 00000001000000000000003F 0/3F323240 0
That's not big numbers, so it's easy to find it writes at 253K/s, but if the number were bigger, it might get hard to read. One of my co-worker, Julien Rouhaud, added a human readable option:
$ ./pgstat -s xlog -H -------- filename -------- -- location -- ---- bytes ---- 00000001000000000000003F 0/3F32EDC0 1011 MB 00000001000000000000003F 0/3F32EDC0 0 bytes 00000001000000000000003F 0/3F32EDC0 0 bytes 00000001000000000000003F 0/3F3ABC78 500 kB 00000001000000000000003F 0/3F491C10 920 kB 00000001000000000000003F 0/3F568548 858 kB 00000001000000000000003F 0/3F634748 817 kB 00000001000000000000003F 0/3F6F4378 767 kB 00000001000000000000003F 0/3F7A56D8 709 kB 00000001000000000000003F 0/3F8413D0 623 kB 00000001000000000000003F 0/3F8D7590 600 kB 00000001000000000000003F 0/3F970160 611 kB 00000001000000000000003F 0/3F9F2840 522 kB 00000001000000000000003F 0/3FA1FD88 181 kB 00000001000000000000003F 0/3FA1FD88 0 bytes 00000001000000000000003F 0/3FA1FD88 0 bytes 00000001000000000000003F 0/3FA1FD88 0 bytes
That's indeed much more readable if you ask me.
Another customer wanted to know how many temporary files were written, and their sizes. Of course, you can get that with the pg_stat_database view, but it only gets added when the query is done. We wanted to know when the query is executed. So I added another report:
$ ./pgstat -s tempfile --- size --- --- count --- 0 0 0 0 13082624 1 34979840 1 56016896 1 56016896 1 56016896 1 0 0 0 0
You see the file being stored.
Well, that's it for now. The 1.0.0 release is available on the github project.
Commentaires
Salut,
Je viens de découvrir. Cet outil est génial. Même ludique, surtout avec -s xlog ou -s tempfile.
