まず、Win7 環境から定番ソフトで確認した結果です。
中古ということで、どのくらい消耗しているのかが気がかりでしたが、SanDisk SSD Dashboard で「余寿命」が 100% でした。入手価格からすれば、よい買い物であったように感じます。
次は、CentOS6 環境で採取した smartctl -a の結果です。
smartctl 5.43 2016-09-28 r4347 [x86_64-linux-2.6.32-696.10.1.el6.x86_64] (local build) Copyright (C) 2002-12 by Bruce Allen, http://smartmontools.sourceforge.net === START OF INFORMATION SECTION === Model Family: Marvell based SanDisk SSDs Device Model: SanDisk SDSSDXPS240G Serial Number: xxxxxxxxx143 LU WWN Device Id: 5 001b44 yyyyyyyyy Firmware Version: X21100RL User Capacity: 240,057,409,536 bytes [240 GB] Sector Size: 512 bytes logical/physical Device is: In smartctl database [for details use: -P show] ATA Version is: 8 ATA Standard is: ACS-2 revision 3 Local Time is: Sat Sep 23 18:53:25 2017 JST SMART support is: Available - device has SMART capability. SMART support is: Enabled === START OF READ SMART DATA SECTION === SMART overall-health self-assessment test result: PASSED General SMART Values: Offline data collection status: (0x00) Offline data collection activity was never started. Auto Offline Data Collection: Disabled. Self-test execution status: ( 0) The previous self-test routine completed without error or no self-test has ever been run. Total time to complete Offline data collection: ( 0) seconds. Offline data collection capabilities: (0x11) SMART execute Offline immediate. No Auto Offline data collection support. Suspend Offline collection upon new command. No Offline surface scan supported. Self-test supported. No Conveyance Self-test supported. No Selective Self-test supported. SMART capabilities: (0x0003) Saves SMART data before entering power-saving mode. Supports SMART auto save timer. Error logging capability: (0x01) Error logging supported. General Purpose Logging supported. Short self-test routine recommended polling time: ( 2) minutes. Extended self-test routine recommended polling time: ( 10) minutes. SMART Attributes Data Structure revision number: 4 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 5 Reallocated_Sector_Ct 0x0032 100 100 --- Old_age Always - 0 9 Power_On_Hours 0x0032 253 100 --- Old_age Always - 707 12 Power_Cycle_Count 0x0032 100 100 --- Old_age Always - 421 166 Min_W/E_Cycle 0x0032 100 100 --- Old_age Always - 1 167 Min_Bad_Block/Die 0x0032 100 100 --- Old_age Always - 45 168 Maximum_Erase_Cycle 0x0032 100 100 --- Old_age Always - 45 169 Total_Bad_Block 0x0032 100 100 --- Old_age Always - 606 171 Program_Fail_Count 0x0032 100 100 --- Old_age Always - 0 172 Erase_Fail_Count 0x0032 100 100 --- Old_age Always - 0 173 Avg_Write/Erase_Count 0x0032 100 100 --- Old_age Always - 14 174 Unexpect_Power_Loss_Ct 0x0032 100 100 --- Old_age Always - 76 184 End-to-End_Error 0x0032 100 100 --- Old_age Always - 0 187 Reported_Uncorrect 0x0032 100 100 --- Old_age Always - 0 188 Command_Timeout 0x0032 100 100 --- Old_age Always - 3 194 Temperature_Celsius 0x0022 070 046 --- Old_age Always - 30 (Min/Max 16/46) 199 SATA_CRC_Error 0x0032 100 100 --- Old_age Always - 0 212 SATA_PHY_Error 0x0032 100 100 --- Old_age Always - 0 230 Perc_Write/Erase_Count 0x0032 100 100 --- Old_age Always - 46 232 Perc_Avail_Resrvd_Space 0x0033 100 100 004 Pre-fail Always - 100 233 Total_NAND_Writes_GiB 0x0032 100 100 --- Old_age Always - 3815 241 Total_Writes_GiB 0x0030 253 253 --- Old_age Offline - 2895 242 Total_Reads_GiB 0x0030 253 253 --- Old_age Offline - 4817 244 Thermal_Throttle 0x0032 000 100 --- Old_age Always - 0 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 No self-tests have been logged. [To run self-tests, use: smartctl -t] Device does not support Selective Self Tests/Logging次は、hdparm -I の結果です。
ATA device, with non-removable media Model Number: SanDisk SDSSDXPS240G Serial Number: xxxxxxxxx143 Firmware Revision: X21100RL Media Serial Num: Media Manufacturer: Transport: Serial, ATA8-AST, SATA 1.0a, SATA II Extensions, SATA Rev 2.5, SATA Rev 2.6, SATA Rev 3.0 Standards: Used: unknown (minor revision code 0x0110) Supported: 9 8 7 6 5 Likely used: 9 Configuration: Logical max current cylinders 16383 65535 heads 16 1 sectors/track 63 63 -- CHS current addressable sectors: 4128705 LBA user addressable sectors: 268435455 LBA48 user addressable sectors: 468862128 Logical Sector size: 512 bytes Physical Sector size: 512 bytes Logical Sector-0 offset: 0 bytes device size with M = 1024*1024: 228936 MBytes device size with M = 1000*1000: 240057 MBytes (240 GB) cache/buffer size = unknown Form Factor: 2.5 inch Nominal Media Rotation Rate: Solid State Device Capabilities: LBA, IORDY(can be disabled) Queue depth: 32 Standby timer values: spec'd by Standard, no device specific minimum R/W multiple sector transfer: Max = 1 Current = 1 Advanced power management level: 128 DMA: mdma0 mdma1 mdma2 udma0 udma1 udma2 udma3 udma4 udma5 *udma6 Cycle time: min=120ns recommended=120ns PIO: pio0 pio1 pio2 pio3 pio4 Cycle time: no flow control=120ns IORDY flow control=120ns Commands/features: Enabled Supported: * SMART feature set Security Mode feature set * Power Management feature set * Write cache * Look-ahead * Host Protected Area feature set * WRITE_BUFFER command * READ_BUFFER command * DOWNLOAD_MICROCODE * Advanced Power Management feature set SET_MAX security extension * 48-bit Address feature set * Device Configuration Overlay feature set * Mandatory FLUSH_CACHE * FLUSH_CACHE_EXT * SMART error logging * SMART self-test * General Purpose Logging feature set * WRITE_{DMA|MULTIPLE}_FUA_EXT * 64-bit World wide name * WRITE_UNCORRECTABLE_EXT command * {READ,WRITE}_DMA_EXT_GPL commands * Segmented DOWNLOAD_MICROCODE * Gen1 signaling speed (1.5Gb/s) * Gen2 signaling speed (3.0Gb/s) * Gen3 signaling speed (6.0Gb/s) * Native Command Queueing (NCQ) * Host-initiated interface power management * Phy event counters * unknown 76[15] * DMA Setup Auto-Activate optimization * Device-initiated interface power management * Software settings preservation unknown 78[8] * Data Set Management TRIM supported (limit 16 blocks) * Deterministic read ZEROs after TRIM Security: Master password revision code = 65534 supported not enabled not locked frozen not expired: security count supported: enhanced erase 2min for SECURITY ERASE UNIT. 18min for ENHANCED SECURITY ERASE UNIT. Logical Unit WWN Device Identifier: 5001b44yyyyyyyyy NAA : 5 IEEE OUI : 001b44 Unique ID : yyyyyyyyy Checksum: correct次は、diskutility での読み込みベンチマーク結果です。
おそらくですが、全領域ゼロ書き込みした状態と思われるので、SecureErase を行いました。
次は、SecureErase 後の diskutility ベンチマークの結果です。ちょっとだけ数値がアップしています。
なお、思わず盲目的に SecureErase をやってしまいましたが、blkdiscard で十分だったかもしれません。