quick notes

docs/_not_used/ext4-ideas.txt

@@ -1,5 +0,0 @@
-ext4
-
-Reduce the inode size: 256 -> -I 128
-
-Reduce the inode ratio: The inode ratio is the number of blocks per inode. You can increase the inode ratio to reduce the number of inodes created. This can be done with the -i option when creating the filesystem. For example, -i 8192 will create one inode every 8192 blocks.

docs/_not_used/extract_ext4.sh

@@ -1,67 +0,0 @@
-#!/usr/bin/env bash
-
-# reference:
-# https://www.kernel.org/doc/Documentation/filesystems/ext4.txt
-# https://wiki.archlinux.org/title/ext4
-#
-# -m reserved-blocks-percentage
-# -F Force mke2fs to create a filesystem, even if the specified device is not a partition on a block special device
-#
-# -O feature
-# from  /etc/mke2fs.conf
-# defaults: has_journal,extent,huge_file,flex_bg,metadata_csum,64bit,dir_nlink,extra_isize
-# disabling journalling, since it's a read-only fs, as well as other unused features
-# extent is actually needed for tail packing small files
-#
-# -E extended-options
-# lazy_itable_init - inode table is fully initialized at the time of file system creation
-# nodiscard - Do not attempt to discard blocks at mkfs time.
-#
-# inode_size = 128 (minimum)
-# inode_ratio = 16384 (default but experimenting)
-
-
-sudo umount mnt || true
-rm -rf mnt
-rm -f image.ext4
-
-
-# make a sparse file
-# make sure it's bigger then the current OSM output
-fallocate -l 200G image.ext4
-
-
-mke2fs -t ext4 -v \
-  -m 0 \
-  -F \
-  -O ^has_journal,^huge_file,^metadata_csum,^64bit,^extra_isize \
-  -E lazy_itable_init=0,nodiscard \
-  -I 128 \
-  -i 16384 \
-  image.ext4
-
-mkdir mnt
-sudo mount -v \
-  -t ext4 \
-  -o nobarrier,noatime \
-  image.ext4 mnt
-
-sudo chown ofm:ofm -R mnt
-
-/data/ofm/venv/bin/python ../../tile_gen/extract.py output.mbtiles mnt/extract \
-  > "extract_out.log" 2> "extract_err.log"
-
-sudo umount mnt
-
-e2fsck -vf image.ext4 && \
-  resize2fs -M image.ext4 && \
-  e2fsck -vf image.ext4
-
-# default to read-only mode
-tune2fs -E mount_opts=ro image.ext4
-
-
-
-
-
-

docs/_not_used/loop_test.sh

@@ -1,13 +0,0 @@
-#!/bin/bash
-
-# Define the source folder
-source_folder="20231228_201550_pt"
-
-# Define the number of copies you want to make
-number_of_copies=40
-
-# Loop and copy the folder into c1, c2, c3, c4, ...
-for i in $(seq 1 $number_of_copies); do
-  cp -r "$source_folder" "c$i"
-  btrfstune -m "c$i/tiles.btrfs"
-done