TL; DR: Nakala hiyo inazungumza juu ya njia rahisi, ya haraka na ya kuaminika ya kutambua programu za Linux zinazoandika data kwenye diski, ambayo husaidia katika kutambua mzigo mkubwa au usio wa kawaida wa mara kwa mara kwenye mfumo mdogo wa disk, na pia inakuwezesha kukadiria juu ya mfumo wa faili. Hii ni kweli hasa kwa SSD katika Kompyuta, EMMC, na kumbukumbu ya Flash katika kompyuta za ubao mmoja.
Wakati wa kuandika makala hii, niligundua kwamba kuandika kilobytes kadhaa za data kwenye mfumo wa faili wa BTRFS husababisha kuandika megabytes 3 za data halisi kwenye diski.
Utangulizi
"Lo, upuuzi, seli za kumbukumbu kwenye SSD za kisasa zitashindwa baada ya miongo kadhaa ya matumizi ya kawaida, usijali kuhusu hilo, ubadilishanaji mdogo wa uhamishaji, mashine za kawaida na folda ya wasifu wa kivinjari kwenye HDD" - jibu la kawaida kwa swali kuhusu kutegemewa kwa viendeshi vya hali dhabiti vilivyo na uhakika wa β150 TBW. Ikiwa unakadiria ni data ngapi programu ya kawaida inaweza kuandika, inaonekana kwamba GB 10-20 kwa siku tayari ni takwimu kubwa, basi iwe na upeo wa GB 40, zaidi zaidi. Kwa kuzingatia nambari hizi, jibu ni sawa - inachukua miaka 10 kufikia uhakika thamani za idadi ya seli zilizofutwa, na 40 GB ya data iliyorekodiwa kila siku.
Hata hivyo, katika miaka 6 tayari ninatumia SSD yangu ya tatu: mtawala wa kwanza alishindwa, na wa pili alianza kuhamisha data kati ya seli mara kadhaa kwa siku, ambayo ilisababisha kuchelewa kwa sekunde 30 katika huduma ya kurekodi.
Baada ya miezi 7 ya kutumia SSD mpya, niliamua kuangalia kiasi cha data iliyoandikwa, kama ilivyoripotiwa na gari yenyewe kupitia SMART.
19.7 TB.
Katika miezi 7 tu, nilitumia 13% ya kiasi kilichohakikishwa cha data iliyorekodiwa, licha ya ukweli kwamba imeundwa kwa mujibu wa mapendekezo ya kuunganisha sehemu na kuanzisha FS, karibu sijawahi kutumia kubadilishana, disks za mashine ziko. kwenye HDD!
Hii ni takwimu kubwa isivyo kawaida; kwa kiwango hiki, dhamana ya TBW itapitwa kabla ya muda wa udhamini wa diski wa miaka 5 kufikiwa. Na kompyuta yangu haiwezi kuandika gigabytes 93 kwa siku! Tunahitaji kuangalia ni data ngapi imeandikwa kwa diski katika dakika 10 ...
Total:
Writes Queued: 24,712, 2,237MiB
Writes Completed: 25,507, 2,237MiB
Write Merges: 58, 5,472KiB
2.2 GiB, oh-ho-ho!
Kuamua kiasi cha data iliyoandikwa kwenye kifaa cha diski
Ikiwa kifaa chako kinasaidia SMART (SSD, EMMC, MicroSD fulani ya viwanda), basi jambo la kwanza unapaswa kufanya ni kuomba data kutoka kwa gari kwa kutumia programu. smartctl, skdump au mmc (kutoka mmc-utils).
Mfano wa pato kutoka kwa mpango wa smartctl
$ sudo smartctl -a /dev/sdb
smartctl 7.0 2019-03-31 r4903 [x86_64-linux-5.3.11-200.fc30.x86_64] (local build)
Copyright (C) 2002-18, Bruce Allen, Christian Franke, www.smartmontools.org
=== START OF INFORMATION SECTION ===
Model Family: Samsung based SSDs
Device Model: Samsung SSD 860 EVO mSATA 250GB
Serial Number: S41MNC0KA13477K
LU WWN Device Id: 5 002538 e700fa64b
Firmware Version: RVT41B6Q
User Capacity: 250β―059β―350β―016 bytes [250 GB]
Sector Size: 512 bytes logical/physical
Rotation Rate: Solid State Device
Form Factor: mSATA
Device is: In smartctl database [for details use: -P show]
ATA Version is: ACS-4 T13/BSR INCITS 529 revision 5
SATA Version is: SATA 3.1, 6.0 Gb/s (current: 3.0 Gb/s)
Local Time is: Tue Nov 19 01:48:50 2019 MSK
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: (0x53) SMART execute Offline immediate.
Auto Offline data collection on/off support.
Suspend Offline collection upon new
command.
No Offline surface scan supported.
Self-test supported.
No Conveyance Self-test supported.
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: ( 85) minutes.
SCT capabilities: (0x003d) SCT Status supported.
SCT Error Recovery Control supported.
SCT Feature Control supported.
SCT Data Table supported.
SMART Attributes Data Structure revision number: 1
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
5 Reallocated_Sector_Ct 0x0033 100 100 010 Pre-fail Always - 0
9 Power_On_Hours 0x0032 098 098 000 Old_age Always - 5171
12 Power_Cycle_Count 0x0032 099 099 000 Old_age Always - 459
177 Wear_Leveling_Count 0x0013 096 096 000 Pre-fail Always - 62
179 Used_Rsvd_Blk_Cnt_Tot 0x0013 100 100 010 Pre-fail Always - 0
181 Program_Fail_Cnt_Total 0x0032 100 100 010 Old_age Always - 0
182 Erase_Fail_Count_Total 0x0032 100 100 010 Old_age Always - 0
183 Runtime_Bad_Block 0x0013 100 100 010 Pre-fail Always - 0
187 Uncorrectable_Error_Cnt 0x0032 100 100 000 Old_age Always - 0
190 Airflow_Temperature_Cel 0x0032 058 039 000 Old_age Always - 42
195 ECC_Error_Rate 0x001a 200 200 000 Old_age Always - 0
199 CRC_Error_Count 0x003e 100 100 000 Old_age Always - 0
235 POR_Recovery_Count 0x0012 099 099 000 Old_age Always - 29
241 Total_LBAs_Written 0x0032 099 099 000 Old_age Always - 38615215765
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]
SMART Selective self-test log data structure revision number 1
SPAN MIN_LBA MAX_LBA CURRENT_TEST_STATUS
1 0 0 Not_testing
2 0 0 Not_testing
3 0 0 Not_testing
4 0 0 Not_testing
5 0 0 Not_testing
Selective self-test flags (0x0):
After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.SSD yangu huhifadhi kiasi cha data iliyoandikwa katika parameta 241 Total_LBAs_Written, katika vizuizi vya kimantiki (LBA) badala ya baiti. Saizi ya kizuizi cha kimantiki katika kesi yangu ni ka 512 (inaweza kuonekana kwenye pato la smartctl, katika saizi ya Sekta). Ili kupata baiti, unahitaji kuzidisha thamani ya parameta na 512.
38615215765 Γ 512 Γ· 1000 Γ· 1000 Γ· 1000 Γ· 1000 = 19,770 Π’Π
38615215765 Γ 512 Γ· 1024 Γ· 1024 Γ· 1024 Γ· 1024 = 17,981 Π’ΠΈΠProgramu ya skdump kwenye SSD yangu inajaribu kutafsiri Jumla_LBAs_Written thamani kwa njia yake mwenyewe, ndiyo sababu inaonyesha 1296217.695 TB, ambayo ni wazi si sahihi.
Ili kujua kiasi cha habari iliyorekodiwa kwenye kiwango cha kifaa, tutatumia programu btrace kutoka kwa kifurushi blktrace. Inaonyesha takwimu za jumla kwa muda wote ambao programu ilikuwa inaendeshwa, na michakato ya mtu binafsi na nyuzi (pamoja na kernels) zilizorekodi.
Tekeleza amri ifuatayo kukusanya habari katika dakika 10, ambapo /dev/sdb ni diski yako:
# btrace -w 600 -a write /dev/sdbPato la kawaida la amri
β¦
8,16 0 3253 50.085433192 0 C WS 125424240 + 64 [0]
8,16 0 3254 50.085550024 0 C WS 193577744 + 64 [0]
8,16 0 3255 50.085685165 0 C WS 197246976 + 64 [0]
8,16 0 3256 50.085936852 0 C WS 125736264 + 128 [0]
8,16 0 3257 50.086060780 0 C WS 96261752 + 64 [0]
8,16 0 3258 50.086195031 0 C WS 94948640 + 64 [0]
8,16 0 3259 50.086327355 0 C WS 124656144 + 64 [0]
8,16 0 3260 50.086843733 15368 C WSM 310218496 + 32 [0]
8,16 0 3261 50.086975238 753 A WSM 310218368 + 32 <- (8,20) 291339904
8,16 0 3262 50.086975560 753 Q WSM 310218368 + 32 [dmcrypt_write/2]
8,16 0 3263 50.086977345 753 G WSM 310218368 + 32 [dmcrypt_write/2]
8,16 0 3264 50.086978072 753 I WSM 310218368 + 32 [dmcrypt_write/2]
8,16 0 3265 50.086979159 753 D WSM 310218368 + 32 [dmcrypt_write/2]
8,16 0 3266 50.087055685 0 C WSM 310218368 + 32 [0]
8,16 0 3267 50.087060168 753 A WSM 310218592 + 160 <- (8,20) 291340128
8,16 0 3268 50.087060367 753 Q WSM 310218592 + 160 [dmcrypt_write/2]
8,16 0 3269 50.087061242 753 G WSM 310218592 + 160 [dmcrypt_write/2]
8,16 0 3270 50.087061698 753 I WSM 310218592 + 160 [dmcrypt_write/2]
8,16 0 3271 50.087062361 753 D WSM 310218592 + 160 [dmcrypt_write/2]
8,16 0 3272 50.087386179 0 C WSM 310218592 + 160 [0]
8,16 0 3273 50.087436417 15368 A FWS 0 + 0 <- (253,1) 0
8,16 0 3274 50.087437471 15368 Q FWS [LS Thread]
8,16 0 3275 50.087440862 15368 G FWS [LS Thread]
8,16 0 3276 50.088300047 0 C WS 0 [0]
8,16 0 3277 50.088470917 753 A WFSM 18882688 + 8 <- (8,20) 4224
8,16 0 3278 50.088471091 753 Q WFSM 18882688 + 8 [dmcrypt_write/2]
8,16 0 3279 50.088471688 753 G WFSM 18882688 + 8 [dmcrypt_write/2]
8,16 0 3280 50.088474334 32254 D WSM 18882688 + 8 [kworker/0:2H]
8,16 0 3281 50.088515572 0 C WSM 18882688 + 8 [0]
8,16 0 3282 50.089229069 0 C WSM 18882688 [0]
CPU0 (8,16):
Reads Queued: 0, 0KiB Writes Queued: 345, 25,932KiB
Read Dispatches: 0, 0KiB Write Dispatches: 331, 25,788KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 0, 0KiB Writes Completed: 1,597, 117,112KiB
Read Merges: 0, 0KiB Write Merges: 1, 16KiB
Read depth: 0 Write depth: 177
IO unplugs: 0 Timer unplugs: 0
CPU1 (8,16):
Reads Queued: 0, 0KiB Writes Queued: 502, 39,948KiB
Read Dispatches: 0, 0KiB Write Dispatches: 495, 40,076KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 0, 0KiB Writes Completed: 0, 0KiB
Read Merges: 0, 0KiB Write Merges: 0, 0KiB
Read depth: 0 Write depth: 177
IO unplugs: 0 Timer unplugs: 0
CPU2 (8,16):
Reads Queued: 0, 0KiB Writes Queued: 297, 26,800KiB
Read Dispatches: 0, 0KiB Write Dispatches: 287, 26,800KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 0, 0KiB Writes Completed: 0, 0KiB
Read Merges: 0, 0KiB Write Merges: 0, 0KiB
Read depth: 0 Write depth: 177
IO unplugs: 0 Timer unplugs: 0
CPU3 (8,16):
Reads Queued: 0, 0KiB Writes Queued: 418, 24,432KiB
Read Dispatches: 0, 0KiB Write Dispatches: 408, 24,448KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 0, 0KiB Writes Completed: 0, 0KiB
Read Merges: 0, 0KiB Write Merges: 2, 272KiB
Read depth: 0 Write depth: 177
IO unplugs: 0 Timer unplugs: 0
Total (8,16):
Reads Queued: 0, 0KiB Writes Queued: 1,562, 117,112KiB
Read Dispatches: 0, 0KiB Write Dispatches: 1,521, 117,112KiB
Reads Requeued: 0 Writes Requeued: 0
Reads Completed: 0, 0KiB Writes Completed: 1,597, 117,112KiB
Read Merges: 0, 0KiB Write Merges: 3, 288KiB
IO unplugs: 0 Timer unplugs: 0
Throughput (R/W): 0KiB/s / 2,338KiB/s
Events (8,16): 9,287 entries
Skips: 0 forward (0 - 0.0%)
btrace inakuwezesha kuona wazi kiasi halisi cha data iliyorekodi, lakini ni vigumu kuelewa ni programu gani zinazorekodi kutoka kwa matokeo yake.
Kuamua mipango inayoandika kwenye gari
Programu ya iotop itaonyesha michakato ya kuandika kwa diski na saizi ya data iliyoandikwa.
Pato rahisi zaidi hutolewa na vigezo vifuatavyo:
# iotop -obPatSampuli ya matokeo ya programu
02:55:47 Total DISK READ : 0.00 B/s | Total DISK WRITE : 30.65 K/s
02:55:47 Actual DISK READ: 0.00 B/s | Actual DISK WRITE: 0.00 B/s
TIME PID PRIO USER DISK READ DISK WRITE SWAPIN IO COMMAND
b'02:55:47 753 be/4 root 0.00 B 0.00 B 0.00 % 0.04 % [dmcrypt_write/2]'
b'02:55:47 788 be/4 root 72.00 K 18.27 M 0.00 % 0.02 % [btrfs-transacti]'
b'02:55:47 15057 be/4 valdikss 216.00 K 283.05 M 0.00 % 0.01 % firefox'
b'02:55:47 1588 ?dif root 0.00 B 0.00 B 0.00 % 0.00 % Xorg -nolisten tcp -auth /var/run/sddm/{398f030f-9667-4dff-b371-81eaae48dfdf} -background none -noreset -displayfd 18 -seat seat0 vt1'
b'02:55:47 15692 be/4 valdikss 988.00 K 9.41 M 0.00 % 0.00 % python3 /usr/bin/gajim'
b'02:55:47 15730 ?dif valdikss 9.07 M 0.00 B 0.00 % 0.00 % telegram-desktop --'
b'02:55:47 2174 ?dif valdikss 1840.00 K 2.47 M 0.00 % 0.00 % yakuake'
b'02:55:47 19827 be/4 root 16.00 K 896.00 K 0.00 % 0.00 % [kworker/u16:7-events_unbound]'
b'02:55:47 19074 be/4 root 16.00 K 480.00 K 0.00 % 0.00 % [kworker/u16:4-btrfs-endio-write]'
b'02:55:47 19006 be/4 root 16.00 K 1872.00 K 0.00 % 0.00 % [kworker/u16:1-events_unbound]'
b'02:55:47 1429 be/4 root 484.00 K 0.00 B 0.00 % 0.00 % accounts-daemon'
b'02:55:47 15820 be/4 valdikss 312.00 K 0.00 B 0.00 % 0.00 % firefox -contentproc -childID 6 -isForBrowser -prefsLen 7894 -prefMapSize 223880 -parentBuildID 20191022164834 -greomni /usr/lib64/firefox/omni.ja -appomni /usr/lib64/firefox/browser/omni.ja -appdir /usr/lib64/firefox/browser 15057 tab'
b'02:55:47 2125 ?dif valdikss 0.00 B 92.00 K 0.00 % 0.00 % plasmashell'
b'02:55:47 1268 be/3 root 0.00 B 4.00 K 0.00 % 0.00 % auditd'
b'02:55:47 1414 be/4 root 0.00 B 4.00 K 0.00 % 0.00 % sssd_nss --uid 0 --gid 0 --logger=files'
b'02:55:47 15238 be/4 valdikss 0.00 B 4.00 K 0.00 % 0.00 % thunderbird'
b'02:55:47 18605 be/4 root 0.00 B 3.19 M 0.00 % 0.00 % [kworker/u16:0-btrfs-endio-write]'
b'02:55:47 18867 be/4 root 0.00 B 96.00 K 0.00 % 0.00 % [kworker/u16:5-btrfs-endio-meta]'
b'02:55:47 19070 be/4 root 0.00 B 160.00 K 0.00 % 0.00 % [kworker/u16:2-btrfs-freespace-write]'
b'02:55:47 19645 be/4 root 0.00 B 2.17 M 0.00 % 0.00 % [kworker/u16:3-events_unbound]'
b'02:55:47 19982 be/4 root 0.00 B 496.00 K 0.00 % 0.00 % [kworker/u16:6-btrfs-endio-write]'Firefox inavutia macho yako, ikirekodi megabaiti 283 katika dakika chache za kukimbia kwa iotop.
Kuamua faili za kuandikiwa
Taarifa kuhusu mchakato ambao unabaka diski ni nzuri, lakini njia ambazo kurekodi hufanywa ni bora zaidi.
Wacha tutumie programu fatrace, ambayo hufuatilia mabadiliko kwenye mfumo wa faili.
# fatrace -f WSampuli ya matokeo ya programu
firefox(15057): CW /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite-wal
firefox(15057): CW /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): CW /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/usage-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/usage
firefox(15057): CW /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/usage
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite-wal
firefox(15057): CW /home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/https+++habr.com/ls/data.sqlite-journal
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqlite
firefox(15057): W /home/valdikss/.mozilla/firefox/xyf4vqh2.default/webappsstore.sqliteFatrace haiwezi kuonyesha kiasi cha data iliyorekodiwa kwa sababu ya utumiaji wa ufuatiliaji rahisi wa ukweli kwamba faili zinapatikana kupitia inotify.
Kutoka kwa matokeo unaweza kuona jinsi Habr huhifadhi nakala yangu kwenye uhifadhi wa ndani wa kivinjari wakati ninaiandika, na vile vile kiendelezi cha Kupiga kwa Kasi ya Kikundi, ambacho, kama tuliweza kugundua kwa kutumia fatrace, husoma data yake kila Sekunde 30. Inasoma, sio kuandika: CW kabla ya faili kusema kuwa faili imefunguliwa kwa kusoma na kuandika, na uundaji wa wakati huo huo wa faili ikiwa haipo (inayoitwa openat na bendera ya O_RDWR|O_CREAT), lakini haisemi kwamba habari yoyote iliandikwa kwa faili.
Ikiwezekana, ili kuhakikisha hili, wacha tutumie strace, na kichungi cha simu za mfumo wa faili:
strace -yy -e trace=open,openat,close,write -f -p 15057 2>&1 | grep extensionPato la amri
[pid 20352] openat(AT_FDCWD, "/home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite", O_RDWR|O_CREAT|O_CLOEXEC, 0644) = 153</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>
[pid 20352] read(153</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>, "SQLite format 3 20 22 @ d 23"..., 100) = 100
[pid 20352] read(153</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>, "SQLite format 3 20 22 @ d 23"..., 4096) = 4096
[pid 20352] openat(AT_FDCWD, "/home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite-wal", O_RDWR|O_CREAT|O_CLOEXEC, 0644) = 166</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite-wal>
β¦
[pid 20352] read(54</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>, " r4304364354354364- 4204!4'414" 250 &"..., 4096) = 4096
[pid 20352] read(54</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>, " 136Pt2262504 O24532016:"16.27 r245306>2461t1q370"..., 4096) = 4096
[pid 20352] close(77</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite-wal>) = 0
[pid 20352] close(54</home/valdikss/.mozilla/firefox/xyf4vqh2.default/storage/default/moz-extension+++e5c304fb-af40-498a-9ba8-47eb0416e933^userContextId=4294967295/idb/3647222921wleabcEoxlt-eengsairo.sqlite>) = 0
Hakuna simu write(), ambayo inaonyesha kuwa hakuna kiingilio kwenye faili.
Kuamua Kichwa cha Mfumo wa Faili
Tofauti kubwa katika usomaji iotop ΠΈ btrace alinipa wazo la kujaribu mfumo wa faili kwa kuandika data kwa faili na kufuatilia usomaji wa btrace.
Ukiondoa kabisa uandishi kwa diski kwa kuingia kwenye hali ya dharura ya mfumo na uandike kwa mikono kaiti kadhaa data kwa faili iliyopo, btrace kwa SSD kutoka btrfs kurekodi ripoti 3 MB data halisi. Mfumo mpya wa faili ulioundwa kwenye kiendeshi cha GB 8 huandika kiwango cha chini cha 264 KB wakati wa kuandika byte moja.
Kwa kulinganisha, kuandika baiti kadhaa kwa faili kwenye ext4 huishia kuandika kilobytes 24 za data kwenye diski.
Mnamo 2017, Jayashree Mohan, Rohan Kadekodi na Vijay Chidambaram , matokeo yao ya btrfs na ext4 kwa 4KB huandika yanaendana na yangu.
Hitimisho na hitimisho
Kupitia udanganyifu ulioelezewa iligunduliwa:
- Kuingia mara kwa mara kwa majimbo ya kazi ya kichapishi na daemon ya kuchapisha ya CUPS hadi /var/cache/ vikombe kila dakika. Shida ilirekebishwa kwa kusafisha /var/nyara/ vikombe (ingawa hakukuwa na kazi za uchapishaji);
- Ukweli kwamba hifadhidata inasomwa kila sekunde 30 na kiendelezi cha Kupiga kwa kasi ya Kikundi kwa Firefox;
- Kuweka kumbukumbu mara kwa mara kwa huduma mbalimbali za ufuatiliaji wa utendaji katika Fedora, na kusababisha megabaiti kadhaa za data kuandikwa kwa btrfs: pmcd.service, pmie.service, pmlogger.service;
- Ukuzaji mkubwa wakati wa kuandika kiasi kidogo cha data kwa kutumia btrfs.
Hitimisho: hupaswi kutumia btrfs ikiwa programu mara nyingi huandika kiasi kidogo cha data (kilobytes chache), vinginevyo itasababisha megabytes ya data iliyoandikwa. Hii ni kweli hasa kwa kompyuta za bodi moja na OS kwenye MicroSD.
Chanzo: mapenzi.com