MTBL_INFO(1)

💖 MTBL_INFO(1) — bestie's guide to peeking inside an MTBL file 💖

okay so you've got an mtbl_info situation and honestly? iconic. this is the mtbl_info page from section 1 of the manual, and it's about to tell you literally everything your MTBL file is hiding. 🎀

✨ NAME ✨

mtbl_info — display information about an MTBL file

like. that's it. that's the job. it shows you info about an MTBL file. slay. 💅

🌸 SYNOPSIS 🌸

mtbl_info FILE [FILE]...

one or more files, bestie. you can pass a whole lil lineup of them and it'll go through each one. no cap. ✨

🦋 DESCRIPTION 🦋

mtbl_info(1) displays the following information about the MTBL files specified on the command line. like, all of it. every stat. it's giving "tell me everything about me" energy and honestly same. 😭

Here's the tea on every single thing it reports:

• file name — the name of the MTBL file. yeah. its name. who it is. 💖
• file size — the total size of the MTBL file, in bytes.
• index bytes — the total number of bytes and proportion of the total file size consumed by the index. so it's double-dipping: raw number and percentage, periodt.
• data block bytes — the total number of bytes and proportion of the total file size consumed by data blocks. same energy, different section.
• data block size — the maximum size of an uncompressed data block. uncompressed, bestie, don't forget that part. 🫶
• data block count — the total number of data blocks. how many. the count. yes.
• entry count — the total number of key-value entries. every single little pair. 👑
• key bytes — the total number of bytes that all keys in the file would occupy if stored end-to-end in a byte array with no delimiters. imagine them all squished together with zero gaps — that's the number.
• value bytes — the total number of bytes that all values in the file would occupy if stored end-to-end in a byte array with no delimiters. same deal, but for the values. ✨
• compression algorithm — the algorithm used to compress data blocks. the possible values are "none", "snappy", "zlib", "lz4", "lz4hc", and "zstd". that's the whole roster, no extras, no surprises. 🌈
• compactness — a rough metric comparing the total number of bytes in the key-value entries with the total size of the MTBL file. it's calculated as (file size) / (key bytes + value bytes), and thus takes into account the gains of data block compression and prefix key compression against the overhead of the index, metadata, and data block offset arrays. so basically: how much glow-up did compression give you vs. how much are the index/metadata/offset arrays eating into it. math but make it fashion. 💅

ngl it's called rough for a reason — it's a rough metric, bestie, not a court ruling. don't @ me. 🙈

and that's the whole page!! mtbl_info(1), from the manual, dated 12/11/2016 — go forth and inspect your files, you absolute main character 🎀💜✨