Linux
刷新程序消耗過多的 CPU
伺服器是 EC2 實例，它代表將文件從 HTTPD 保存到 NAS (NFS)。
像 flush-0:32 這樣的程序消耗超過 %90 的 CPU 和平均負載：65.50、64.02、66.59。
根據圖表，它每天都在增加，而初始負載平均值在 4 個核心上約為 1.01、2.02、1.80。我在負載均衡器下添加了另一個類似的實例，其 CPU 使用率僅為 %6 ATM。
這些刷新過程究竟做了什麼？
如果客戶端只需要寫入數據，也許我們應該關閉 NFS 屬性記憶體？
這可能是因為數據包碎片嗎？
以下是一些統計數據
nfsstat -s -4：================================================================= Server 0: Server rpc stats: calls badcalls badauth badclnt xdrcall 715054137 0 0 0 0 Server nfs v4: null compound 993 0% 715053143 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 143229323 6% 78092765 3% 36693816 1% create delegpurge delegreturn getattr getfh link 3486926 0% 0 0% 0 0% 679872421 28% 158406682 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 95872524 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 78173920 3% 0 0% 46442107 1% 1668 0% 715044032 29% 0 0% putrootfh read readdir readlink remove rename 7110 0% 42081145 1% 9116904 0% 0 0% 7026 0% 1257 0% renew restorefh savefh secinfo setattr setcltid 14 0% 81591622 3% 81659244 3% 0 0% 21028018 0% 3244 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3244 0% 0 0% 114086560 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 1: Server rpc stats: calls badcalls badauth badclnt xdrcall 307172153 0 0 0 0 Server nfs v4: null compound 427 0% 307171725 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 58451998 5% 32717934 3% 15557564 1% create delegpurge delegreturn getattr getfh link 1424670 0% 0 0% 0 0% 291829363 28% 67959378 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 41790934 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 32741459 3% 0 0% 18993781 1% 75 0% 307167167 30% 0 0% putrootfh read readdir readlink remove rename 3108 0% 18598329 1% 3892199 0% 0 0% 742 0% 2 0% renew restorefh savefh secinfo setattr setcltid 3 0% 34142743 3% 34166131 3% 0 0% 8963430 0% 1449 0% setcltidconf verify write rellockowner bc_ctl bind_conn 1449 0% 0 0% 54628017 5% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 2: Server rpc stats: calls badcalls badauth badclnt xdrcall 53026598 0 0 0 0 Server nfs v4: null compound 89 0% 53026508 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 9605179 5% 5472897 3% 2633853 1% create delegpurge delegreturn getattr getfh link 231276 0% 0 0% 0 0% 50395149 28% 11903036 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 7528324 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 5477948 3% 0 0% 2760996 1% 15 0% 53025580 30% 0 0% putrootfh read readdir readlink remove rename 633 0% 3566001 2% 673466 0% 0 0% 11 0% 0 0% renew restorefh savefh secinfo setattr setcltid 2 0% 5704253 3% 5709223 3% 0 0% 1526967 0% 292 0% setcltidconf verify write rellockowner bc_ctl bind_conn 292 0% 0 0% 10439844 5% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 3: Server rpc stats: calls badcalls badauth badclnt xdrcall 63045403 0 0 0 0 Server nfs v4: null compound 121 0% 63045280 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 11504749 5% 6504139 3% 3119453 1% create delegpurge delegreturn getattr getfh link 271128 0% 0 0% 0 0% 59865633 28% 14058385 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 8852565 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 6521385 3% 0 0% 3365913 1% 15 0% 63043988 30% 0 0% putrootfh read readdir readlink remove rename 874 0% 4209822 2% 791702 0% 0 0% 6 0% 0 0% renew restorefh savefh secinfo setattr setcltid 9 0% 6775367 3% 6792509 3% 0 0% 1811226 0% 409 0% setcltidconf verify write rellockowner bc_ctl bind_conn 409 0% 0 0% 12368747 5% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 4: Server rpc stats: calls badcalls badauth badclnt xdrcall 817288490 0 0 0 0 Server nfs v4: null compound 1204 0% 817287285 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 164320609 6% 89471711 3% 42448842 1% create delegpurge delegreturn getattr getfh link 4101436 0% 0 0% 0 0% 778155935 28% 180629867 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 109104313 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 89598740 3% 0 0% 53534516 1% 9727 0% 817288175 29% 0 0% putrootfh read readdir readlink remove rename 8020 0% 46348481 1% 10773529 0% 0 0% 100880 0% 12342 0% renew restorefh savefh secinfo setattr setcltid 80 0% 93709338 3% 93712518 3% 0 0% 24303185 0% 3352 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3352 0% 0 0% 127464001 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 5: Server rpc stats: calls badcalls badauth badclnt xdrcall 804660319 0 0 0 0 Server nfs v4: null compound 1204 0% 804659114 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 161331719 6% 88318366 3% 41571552 1% create delegpurge delegreturn getattr getfh link 4090384 0% 0 0% 0 0% 764533960 28% 177969216 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 107385644 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 88321805 3% 0 0% 54307425 2% 444 0% 804647492 29% 0 0% putrootfh read readdir readlink remove rename 8353 0% 45980723 1% 10410930 0% 0 0% 88471 0% 440 0% renew restorefh savefh secinfo setattr setcltid 21 0% 92410970 3% 92412629 3% 0 0% 23733174 0% 3688 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3688 0% 0 0% 125268800 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 6: Server rpc stats: calls badcalls badauth badclnt xdrcall 795385017 0 0 0 0 Server nfs v4: null compound 1204 0% 795383812 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 158633282 5% 87331357 3% 41400927 1% create delegpurge delegreturn getattr getfh link 4080179 0% 0 0% 0 0% 756063664 28% 176355823 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 106692513 4% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 87333398 3% 0 0% 53591273 2% 187 0% 795371861 29% 0 0% putrootfh read readdir readlink remove rename 8367 0% 45030006 1% 10352133 0% 0 0% 80473 0% 151 0% renew restorefh savefh secinfo setattr setcltid 28 0% 91411943 3% 91413728 3% 0 0% 23629833 0% 3707 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3707 0% 0 0% 124033436 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 7: Server rpc stats: calls badcalls badauth badclnt xdrcall 801916264 0 0 0 0 Server nfs v4: null compound 1204 0% 801915059 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 161888929 6% 88285947 3% 41212864 1% create delegpurge delegreturn getattr getfh link 4069479 0% 0 0% 0 0% 762072130 28% 177131560 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 106437411 3% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 88288337 3% 0 0% 54779036 2% 191 0% 801903449 29% 0 0% putrootfh read readdir readlink remove rename 8225 0% 45488312 1% 10259565 0% 0 0% 76243 0% 177 0% renew restorefh savefh secinfo setattr setcltid 4 0% 92355900 3% 92357993 3% 0 0% 23515286 0% 3558 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3558 0% 0 0% 123741908 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 8: Server rpc stats: calls badcalls badauth badclnt xdrcall 804732833 1 1 0 0 Server nfs v4: null compound 1204 0% 804731628 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 161428939 6% 88340891 3% 41568432 1% create delegpurge delegreturn getattr getfh link 4085332 0% 0 0% 0 0% 764396486 28% 177796853 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 107176837 3% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 88342790 3% 0 0% 54344886 2% 187 0% 804720008 29% 0 0% putrootfh read readdir readlink remove rename 8226 0% 46219141 1% 10381361 0% 0 0% 83380 0% 160 0% renew restorefh savefh secinfo setattr setcltid 0 0% 92426602 3% 92428282 3% 0 0% 23736349 0% 3554 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3554 0% 0 0% 125088530 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0% ================================================================= Server 9: Server rpc stats: calls badcalls badauth badclnt xdrcall 800961003 0 0 0 0 Server nfs v4: null compound 1204 0% 800959798 99% Server nfs v4 operations: op0-unused op1-unused op2-future access close commit 0 0% 0 0% 0 0% 161394704 6% 88264733 3% 41642226 1% create delegpurge delegreturn getattr getfh link 4098314 0% 0 0% 0 0% 761225542 28% 172733291 6% 0 0% lock lockt locku lookup lookup_root nverify 0 0% 0 0% 0 0% 102217363 3% 0 0% 0 0% open openattr open_conf open_dgrd putfh putpubfh 88272429 3% 0 0% 53937975 2% 467 0% 800948292 30% 0 0% putrootfh read readdir readlink remove rename 8312 0% 45893437 1% 10409370 0% 0 0% 83127 0% 478 0% renew restorefh savefh secinfo setattr setcltid 35 0% 92369729 3% 92371221 3% 0 0% 23772628 0% 3637 0% setcltidconf verify write rellockowner bc_ctl bind_conn 3637 0% 0 0% 124997490 4% 0 0% 0 0% 0 0% exchange_id create_ses destroy_ses free_stateid getdirdeleg getdevinfo 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% getdevlist layoutcommit layoutget layoutreturn secinfononam sequence 0 0% 0 0% 0 0% 0 0% 0 0% 0 0% set_ssv test_stateid want_deleg destroy_clid reclaim_comp 0 0% 0 0% 0 0% 0 0% 0 0%
刷新程序負責管理將臟頁寫回它們來自的文件系統。它們永遠不應該佔用太多 CPU；他們的大部分時間都花在等待磁碟（或 NFS 等網路）上。如果您在刷新過程中看到 CPU 使用率很高，則可能是核心錯誤 - 嘗試重新啟動，這應該會清除狀態。