bcache_vs_lvmcache zfs sync disabled bcache_default: Processor: Intel Core i5-4590 @ 3.70GHz (4 Cores), Motherboard: MSI Z97-G43 (MS-7816) v3.0, Chipset: Intel 4th Gen Core DRAM, Memory: 2048MB, Disk: 2 x 4001GB Western Digital WD40EFRX-68W + 240GB ADATA SP550 + 240GB INTEL SSDSC2BW24, Graphics: Intel HD 4600, Audio: Intel Xeon E3-1200 v3/4th, Network: Realtek RTL8111/8168/8411 OS: Ubuntu 16.04, Kernel: 4.4.0-21-generic (x86_64), Desktop: Xfce 4.12, Display Server: X Server 1.18.3, Display Driver: intel 2.99.917, Compiler: GCC 5.4.0 20160609, File-System: overlayfs, Screen Resolution: 2560x1440 lvmcache_default: Processor: Intel Core i5-4590 @ 3.70GHz (4 Cores), Motherboard: MSI Z97-G43 (MS-7816) v3.0, Chipset: Intel 4th Gen Core DRAM, Memory: 2048MB, Disk: 2 x 4001GB Western Digital WD40EFRX-68W + 240GB ADATA SP550 + 240GB INTEL SSDSC2BW24, Graphics: Intel HD 4600, Audio: Intel Xeon E3-1200 v3/4th, Network: Realtek RTL8111/8168/8411 OS: Ubuntu 16.04, Kernel: 4.4.0-21-generic (x86_64), Desktop: Xfce 4.12, Display Server: X Server 1.18.3, Display Driver: intel 2.99.917, Compiler: GCC 5.4.0 20160609, File-System: overlayfs, Screen Resolution: 2560x1440 lvmcahche_zfs-sync-disabled: Processor: Intel Core i5-4590 @ 3.70GHz (4 Cores), Motherboard: MSI Z97-G43 (MS-7816) v3.0, Chipset: Intel 4th Gen Core DRAM, Memory: 2048MB, Disk: 2 x 4001GB Western Digital WD40EFRX-68W + 240GB ADATA SP550 + 240GB INTEL SSDSC2BW24, Graphics: Intel HD 4600, Audio: Intel Xeon E3-1200 v3/4th, Network: Realtek RTL8111/8168/8411 OS: Ubuntu 16.04, Kernel: 4.4.0-21-generic (x86_64), Desktop: Xfce 4.12, Display Server: X Server 1.18.3, Display Driver: intel 2.99.917, Compiler: GCC 5.4.0 20160609, File-System: overlayfs, Screen Resolution: 2560x1440 AIO-Stress 0.21 Test: Random Write MB/s > Higher Is Better bcache_default .............. 702.56 |========================================= lvmcache_default ............ 579.86 |================================== lvmcahche_zfs-sync-disabled . 377.83 |====================== Flexible IO Tester 2.1.11 Test: Example Network Job - Disk Target: Default Test Directory Seconds (Run Time) < Lower Is Better bcache_default .............. 24.77 |======================================= lvmcache_default ............ 27.01 |========================================== lvmcahche_zfs-sync-disabled . 25.92 |======================================== Flexible IO Tester 2.1.11 Test: Intel IOMeter File Server Access Pattern - Disk Target: Default Test Directory Seconds (Run Time) < Lower Is Better bcache_default .............. 76.34 |============================== lvmcache_default ............ 103.15 |========================================= lvmcahche_zfs-sync-disabled . 99.41 |======================================== SQLite 3.8.10.2 Test Target: Default Test Directory Seconds < Lower Is Better bcache_default ... 37.45 |======= lvmcache_default . 286.09 |==================================================== FS-Mark 3.3 Test: 1000 Files, 1MB Size Files/s > Higher Is Better bcache_default .............. 52.52 |=== lvmcache_default ............ 18.05 |= lvmcahche_zfs-sync-disabled . 629.52 |========================================= FS-Mark 3.3 Test: 1000 Files, 1MB Size, No Sync/FSync Files/s > Higher Is Better bcache_default .............. 278.62 |================== lvmcache_default ............ 621.77 |========================================= lvmcahche_zfs-sync-disabled . 563.33 |===================================== Dbench 4.0 Client Count: 1 MB/s > Higher Is Better bcache_default .............. 57.64 |=== lvmcache_default ............ 55.67 |=== lvmcahche_zfs-sync-disabled . 768.93 |========================================= IOzone 3.405 Record Size: 4Kb - File Size: 512MB - Disk Test: Read Performance MB/s > Higher Is Better bcache_default .............. 856.66 |======================================== lvmcache_default ............ 842.92 |======================================= lvmcahche_zfs-sync-disabled . 885.72 |========================================= IOzone 3.405 Record Size: 4Kb - File Size: 512MB - Disk Test: Write Performance MB/s > Higher Is Better bcache_default .............. 142.96 |========== lvmcache_default ............ 314.40 |===================== lvmcahche_zfs-sync-disabled . 612.11 |========================================= Threaded I/O Tester 20170503 Test: Read - Size Per Thread: 32MB - Thread Count: 4 MB/s > Higher Is Better bcache_default .............. 1803.91 |=================================== lvmcache_default ............ 2037.13 |======================================== lvmcahche_zfs-sync-disabled . 1585.21 |=============================== Threaded I/O Tester 20170503 Test: Write - Size Per Thread: 32MB - Thread Count: 4 MB/s > Higher Is Better bcache_default .............. 1.93 | lvmcache_default ............ 1.41 | lvmcahche_zfs-sync-disabled . 905.82 |========================================= Threaded I/O Tester 20170503 Test: Random Read - Size Per Thread: 32MB - Thread Count: 4 MB/s > Higher Is Better bcache_default .............. 3433.09 |============ lvmcache_default ............ 3303.92 |=========== lvmcahche_zfs-sync-disabled . 11305.83 |======================================= Threaded I/O Tester 20170503 Test: Random Write - Size Per Thread: 32MB - Thread Count: 4 MB/s > Higher Is Better bcache_default .............. 14.09 | lvmcache_default ............ 70.81 | lvmcahche_zfs-sync-disabled . 7964.40 |======================================== Compile Bench 0.6 Test: Compile MB/s > Higher Is Better bcache_default .............. 638.64 |========================================= lvmcache_default ............ 445.67 |============================= lvmcahche_zfs-sync-disabled . 473.40 |============================== Compile Bench 0.6 Test: Initial Create MB/s > Higher Is Better bcache_default .............. 204.36 |========================================= lvmcache_default ............ 137.52 |============================ lvmcahche_zfs-sync-disabled . 135.76 |=========================== Compile Bench 0.6 Test: Read Compiled Tree MB/s > Higher Is Better bcache_default .............. 600.52 |========================================= lvmcache_default ............ 548.14 |===================================== lvmcahche_zfs-sync-disabled . 376.26 |========================== PostMark 1.51 Disk Transaction Performance TPS > Higher Is Better bcache_default .............. 512 |============================================ lvmcache_default ............ 325 |============================ lvmcahche_zfs-sync-disabled . 319 |=========================== PostgreSQL pgbench 9.6.3 Scaling: On-Disk - Test: Normal Load - Mode: Read Write TPS > Higher Is Better bcache_default .............. 119.84 |========= lvmcache_default ............ 203.32 |=============== lvmcahche_zfs-sync-disabled . 541.09 |========================================= PostgreSQL pgbench 9.6.3 Scaling: Mostly RAM - Test: Normal Load - Mode: Read Write TPS > Higher Is Better bcache_default .............. 350.49 |========= lvmcache_default ............ 118.14 |=== lvmcahche_zfs-sync-disabled . 1580.37 |======================================== PostgreSQL pgbench 9.6.3 Scaling: Buffer Test - Test: Normal Load - Mode: Read Write TPS > Higher Is Better bcache_default .............. 761.57 |=== lvmcache_default ............ 229.57 |= lvmcahche_zfs-sync-disabled . 9962.37 |======================================== PostgreSQL pgbench 9.6.3 Scaling: On-Disk - Test: Heavy Contention - Mode: Read Write TPS > Higher Is Better bcache_default .............. 189.12 |============== lvmcache_default ............ 231.79 |================= lvmcahche_zfs-sync-disabled . 565.18 |=========================================