archbuild: update systemd-swap config to reflect upstream changes

roles/archbuild/files/swap.conf

@@ -17,7 +17,7 @@
 zswap_enabled=1
 zswap_compressor=lz4      # lzo lz4
 zswap_max_pool_percent=25 # 1-99
-zswap_zpool=z3fold        # zbud z3fold
+zswap_zpool=zbud          # zbud z3fold
 
 ################################################################################
 # ZRam
@@ -27,62 +27,28 @@ zswap_zpool=z3fold        # zbud z3fold
 # https://www.kernel.org/doc/Documentation/blockdev/zram.txt
 
 zram_enabled=0
-zram_size=$(($ram_size/4))K     # This is 1/4 of ram size by default.
-zram_streams=$cpu_count
+zram_size=$(($RAM_SIZE/4))      # This is 1/4 of ram size by default.
+zram_streams=$NCPU
 zram_alg=lz4                    # lzo lz4 deflate lz4hc 842 - for Linux 4.8.4
 zram_prio=32767                 # 1 - 32767
 
-################################################################################
-# Swap File Universal
-# loop + swapfile = support any fs (also btrfs)
-swapfu_enabled=1
-# File is sparse and dynamically allocated.
-swapfu_size=${ram_size}K # Size of swap file.
-# But you may don't like it, ex. in a case when you don't have much free space
-swapfu_preallocated=0
-# Don't use cow (btrfs)
-swapfu_nocow=1
-# Set directio for loop device
-# If enabled, can be more safe in case of memory OOM
-swapfu_directio=0
-# Test setup:
-# files with size 2G (mounted by loop), fs: btrfs
-# fio: test 4k, randrw, iodepth 64, libaio, directio 1
-# HDD 1TB 5400k
-# Loop device:
-# PREALLOC | NoCoW | DirectIO | ~ IO/s | Comment
-#    -     |   -   |    -     |   2400 | NOT stable speed
-#    +     |   -   |    -     |    160 | stable speed, HORRIBLY SLOW
-#    -     |   +   |    -     |   3300 | stable speed, can degraded by time
-#    +     |   +   |    -     |   2000 | stable speed
-#    -     |   -   |    +     |     50 | not stable speed
-#    +     |   -   |    +     |     69 | not stable speed
-#    -     |   +   |    +     |     63 | not stable speed
-#    +     |   +   |    +     |     75 | not stable speed
-# raw file (loop device are slow):
-# PREALLOC | NoCoW | DirectIO | ~ IO/s | Comment
-#    -     |   -   |    +     |   7600 | not stable speed
-#    +     |   -   |    +     |     69 | not stable speed
-#    -     |   +   |    +     |  13000 | not stable speed
-#    +     |   +   |    +     |    174 | not stable speed
-
-# File will not be available in fs after script start
-# Make sure what script can access to this path during the boot process.
-# Full path to swapfile
-swapfu_path=/var/lib/systemd-swap/swapfu
-swapfu_prio=1     # 1 - 32767
-
 ################################################################################
 # Swap File Chunked
 # Allocate swap files dynamically
-# Min swap size 256M, Max 16*256M
-swapfc_enabled=0
+# For btrfs fallback to swapfile + loop will be used
+# ex. Min swap size 512M, Max 8*512M
+swapfc_enabled=1
+swapfc_force_use_loop=0     # Force usage of swapfile + loop
 swapfc_frequency=1s         # How often check free swap space
-swapfc_chunk_size=256M      # Allocate size of swap chunk
-swapfc_max_count=16         # 0 - unlimited, note: 32 is a kernel maximum
+swapfc_chunk_size=512M      # Allocate size of swap chunk
+swapfc_max_count=8          # 0 - unlimited, note: 32 is a kernel maximum
 swapfc_free_swap_perc=15    # Add new chunk if free < 15%
                             # Remove chunk if free > 15+40% & chunk count > 2
 swapfc_path=/var/lib/systemd-swap/swapfc/
+# Only for swapfile + loop
+swapfc_nocow=1              # Disable CoW on swapfile
+swapfc_directio=1           # Use directio for loop dev
+swapfc_force_preallocated=0 # Will preallocate created files
 
 ################################################################################
 # Swap devices