The first is the 4GB SSD and the second is the 8GB SSD inside my EEE 901 netbook. These old SSDs seem to be from the dumper side of SSD market and behave more like dump flash with little controller interference.
My guess for the 4GB SSD: erase size 1 Megabyte, page size 2048 Byte
My guess for the 8GB SSD: erase size 2 Megabyte, page size 2048 Byte
Both perform well with up to 9 au, though 8 give a little more speed.
Now I would only need to know how to translate this into fitting stride/stripe values...
root@Microknoppix:/tmp/flashbench-HEAD-2e30b19# ./flashbench -a /dev/sda --blocksize=1024 align 1073741824 pre 641µs on 792µs post 567µs diff 187µs align 536870912 pre 683µs on 851µs post 577µs diff 221µs align 268435456 pre 657µs on 847µs post 564µs diff 236µs align 134217728 pre 626µs on 794µs post 525µs diff 218µs align 67108864 pre 666µs on 836µs post 582µs diff 212µs align 33554432 pre 573µs on 732µs post 571µs diff 160µs align 16777216 pre 577µs on 738µs post 572µs diff 163µs align 8388608 pre 565µs on 740µs post 563µs diff 176µs align 4194304 pre 580µs on 735µs post 562µs diff 164µs align 2097152 pre 552µs on 706µs post 522µs diff 169µs align 1048576 pre 565µs on 734µs post 547µs diff 178µs align 524288 pre 548µs on 640µs post 542µs diff 94.7µs align 262144 pre 546µs on 639µs post 540µs diff 96.1µs align 131072 pre 547µs on 640µs post 541µs diff 96.1µs align 65536 pre 536µs on 629µs post 528µs diff 96.7µs align 32768 pre 535µs on 626µs post 526µs diff 95.6µs align 16384 pre 534µs on 627µs post 527µs diff 97.2µs align 8192 pre 558µs on 654µs post 554µs diff 98µs align 4096 pre 536µs on 633µs post 528µs diff 101µs align 2048 pre 549µs on 546µs post 550µs diff -3781ns root@Microknoppix:/tmp/flashbench-HEAD-2e30b19# ./flashbench -a /dev/sdb --blocksize=1024 align 2147483648 pre 740µs on 890µs post 628µs diff 207µs align 1073741824 pre 732µs on 898µs post 603µs diff 231µs align 536870912 pre 740µs on 913µs post 590µs diff 248µs align 268435456 pre 716µs on 890µs post 596µs diff 234µs align 134217728 pre 694µs on 858µs post 586µs diff 218µs align 67108864 pre 598µs on 771µs post 575µs diff 184µs align 33554432 pre 619µs on 788µs post 590µs diff 184µs align 16777216 pre 624µs on 791µs post 591µs diff 184µs align 8388608 pre 613µs on 776µs post 578µs diff 180µs align 4194304 pre 619µs on 781µs post 584µs diff 179µs align 2097152 pre 617µs on 782µs post 574µs diff 187µs align 1048576 pre 631µs on 756µs post 632µs diff 125µs align 524288 pre 634µs on 747µs post 634µs diff 113µs align 262144 pre 619µs on 717µs post 599µs diff 108µs align 131072 pre 603µs on 722µs post 601µs diff 120µs align 65536 pre 627µs on 748µs post 629µs diff 120µs align 32768 pre 619µs on 743µs post 628µs diff 119µs align 16384 pre 619µs on 736µs post 621µs diff 116µs align 8192 pre 622µs on 733µs post 617µs diff 114µs align 4096 pre 598µs on 721µs post 587µs diff 128µs align 2048 pre 596µs on 596µs post 598µs diff -1092ns