WD Blue 510 SSD and strange write performance
Date: Thu, 14 Mar 2024 18:47:01 UTC
This might be more of a hardware question than anything, but I noticed the drive is fairly fast on initial writes, but dramatically slows down over time with a consistent write. At bootup time, I can blast out a file (UFS2 mount) # dd if=/dev/zero of=/mnt/tmp/junk.bin.`date "+%s"` bs=1m status=progress count=4000 3735027712 bytes (3735 MB, 3562 MiB) transferred 7.014s, 533 MB/s # nice and fast. But subsequent writes really start to tank. # dd if=/dev/zero of=/mnt/tmp/junk.bin.`date "+%s"` bs=1m status=progress count=4000 4128243712 bytes (4128 MB, 3937 MiB) transferred 46.048s, 90 MB/s # dd if=/dev/zero of=/mnt/tmp/junk.bin.`date "+%s"` bs=1m status=progress count=4000 3992977408 bytes (3993 MB, 3808 MiB) transferred 31.016s, 129 MB/s If I wait for 2min, it seems to be back to normal # sleep 120 ; dd if=/dev/zero of=/mnt/tmp/junk.bin.`date "+%s"` bs=1m status=progress count=4000 4137680896 bytes (4138 MB, 3946 MiB) transferred 9.025s, 458 MB/s Is there something going on behind the scenes limiting the amount of sustained writes these drives can handle ? Is it just a limitation of the SSD ? I didnt notice such issues on some consumer Samsungs. The problem initially showed up for me when I was doing a series of zfs send | zfs recv on the same pool (so a lot of reads and writes at the same time) and I would get a bunch of errors on the WD disks. Replacing them with Samsungs avoids the errors. === START OF INFORMATION SECTION === Device Model: WD Blue SA510 2.5 1000GB Serial Number: 240406800001 LU WWN Device Id: 5 001b44 8b334e00b Firmware Version: 52046100 User Capacity: 1,000,204,886,016 bytes [1.00 TB] Sector Size: 512 bytes logical/physical Rotation Rate: Solid State Device Form Factor: 2.5 inches TRIM Command: Available, deterministic Device is: Not in smartctl database 7.3/5528 ATA Version is: ACS-4, ACS-2 T13/2015-D revision 3 SATA Version is: SATA 3.2, 6.0 Gb/s (current: 6.0 Gb/s) Local Time is: Thu Mar 14 14:41:58 2024 EDT SMART support is: Available - device has SMART capability. SMART support is: Enabled # camcontrol iden ada1 pass1: <WD Blue SA510 2.5 1000GB 52046100> ACS-4 ATA SATA 3.x device pass1: 600.000MB/s transfers (SATA 3.x, UDMA6, PIO 512bytes) protocol ACS-4 ATA SATA 3.x device model WD Blue SA510 2.5 1000GB firmware revision 52046100 serial number 240406800001 WWN 5001b448b334e00b additional product id cylinders 16383 heads 16 sectors/track 63 sector size logical 512, physical 512, offset 0 LBA supported 268435455 sectors LBA48 supported 1953525168 sectors PIO supported PIO4 DMA supported WDMA2 UDMA6 media RPM non-rotating Zoned-Device Commands no Feature Support Enabled Value Vendor read ahead yes yes write cache yes yes flush cache yes yes Native Command Queuing (NCQ) yes 32 tags NCQ Priority Information no NCQ Non-Data Command no NCQ Streaming no Receive & Send FPDMA Queued no NCQ Autosense no SMART yes yes security yes no power management yes yes microcode download yes yes advanced power management yes no 0/0x00 automatic acoustic management no no media status notification no no power-up in Standby no no write-read-verify no no unload no no general purpose logging yes yes free-fall no no sense data reporting no no extended power conditions no no device statistics notification no no Data Set Management (DSM/TRIM) yes DSM - max 512byte blocks yes 8 DSM - deterministic read yes any value Trusted Computing no encrypts all user data no Sanitize yes block, Sanitize - commands allowed yes Sanitize - antifreeze lock yes Host Protected Area (HPA) no Accessible Max Address Config yes no 1953525168/1953525168 RELENG_14 from today