€•LŒsphinx.addnodes”Œdocument”“”)”}”(Œ rawsource”Œ”Œchildren”]”(Œ translations”Œ LanguagesNode”“”)”}”(hhh]”(hŒ pending_xref”“”)”}”(hhh]”Œdocutils.nodes”ŒText”“”ŒChinese (Simplified)”…””}”Œparent”hsbaŒ attributes”}”(Œids”]”Œclasses”]”Œnames”]”Œdupnames”]”Œbackrefs”]”Œ refdomain”Œstd”Œreftype”Œdoc”Œ reftarget”Œ=/translations/zh_CN/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuŒtagname”hhh ubh)”}”(hhh]”hŒChinese (Traditional)”…””}”hh2sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/zh_TW/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒItalian”…””}”hhFsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/it_IT/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒJapanese”…””}”hhZsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/ja_JP/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒKorean”…””}”hhnsbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/ko_KR/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒPortuguese (Brazilian)”…””}”hh‚sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/pt_BR/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubh)”}”(hhh]”hŒSpanish”…””}”hh–sbah}”(h]”h ]”h"]”h$]”h&]”Œ refdomain”h)Œreftype”h+Œ reftarget”Œ=/translations/sp_SP/admin-guide/device-mapper/dm-service-time”Œmodname”NŒ classname”NŒ refexplicit”ˆuh1hhh ubeh}”(h]”h ]”h"]”h$]”h&]”Œcurrent_language”ŒEnglish”uh1h hhŒ _document”hŒsource”NŒline”NubhŒsection”“”)”}”(hhh]”(hŒtitle”“”)”}”(hŒdm-service-time”h]”hŒdm-service-time”…””}”(hh¼h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhh·h²hh³ŒW/var/lib/git/docbuild/linux/Documentation/admin-guide/device-mapper/dm-service-time.rst”h´KubhŒ paragraph”“”)”}”(hŒ˜dm-service-time is a path selector module for device-mapper targets, which selects a path with the shortest estimated service time for the incoming I/O.”h]”hŒ˜dm-service-time is a path selector module for device-mapper targets, which selects a path with the shortest estimated service time for the incoming I/O.”…””}”(hhÍh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khh·h²hubhÌ)”}”(hX The service time for each path is estimated by dividing the total size of in-flight I/Os on a path with the performance value of the path. The performance value is a relative throughput value among all paths in a path-group, and it can be specified as a table argument.”h]”hX The service time for each path is estimated by dividing the total size of in-flight I/Os on a path with the performance value of the path. The performance value is a relative throughput value among all paths in a path-group, and it can be specified as a table argument.”…””}”(hhÛh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K hh·h²hubhÌ)”}”(hŒ)The path selector name is 'service-time'.”h]”hŒ-The path selector name is ‘service-time’.”…””}”(hhéh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khh·h²hubhÌ)”}”(hŒTable parameters for each path:”h]”hŒTable parameters for each path:”…””}”(hh÷h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khh·h²hubhŒ block_quote”“”)”}”(hXÊ[ []] : The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table. : The relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available. ”h]”hŒdefinition_list”“”)”}”(hhh]”hŒdefinition_list_item”“”)”}”(hXš[ []] : The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table. : The relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available. ”h]”(hŒterm”“”)”}”(hŒ([ []]”h]”hŒ([ []]”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´KhjubhŒ definition”“”)”}”(hhh]”j )”}”(hhh]”(j)”}”(hŒÇ: The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table.”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hj2h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khj.ubj')”}”(hhh]”hÌ)”}”(hŒ·The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table.”h]”hŒ·The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table.”…””}”(hjCh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khj@ubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hj.ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khj+ubj)”}”(hX : The relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available. ”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hjah²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khj]ubj')”}”(hhh]”hÌ)”}”(hŒñThe relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available.”h]”hŒûThe relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value ‘1’ is used. If ‘0’ is given, the path isn’t selected while other paths having a positive value are available.”…””}”(hjrh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´Khjoubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hj]ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khj+ubeh}”(h]”h ]”h"]”h$]”h&]”uh1j hj(ubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khj ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hjubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´Khh·h²hubhÌ)”}”(hŒStatus for each path:”h]”hŒStatus for each path:”…””}”(hjªh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K hh·h²hubj)”}”(hX“ : 'A' if the path is active, 'F' if the path is failed. : The number of path failures. : The size of in-flight I/Os on the path. : The relative throughput value of the path among all paths in the path-group. ”h]”j )”}”(hhh]”j)”}”(hXo : 'A' if the path is active, 'F' if the path is failed. : The number of path failures. : The size of in-flight I/Os on the path. : The relative throughput value of the path among all paths in the path-group. ”h]”(j)”}”(hŒ< ”h]”hŒ< ”…””}”(hjÃh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K,hj¿ubj')”}”(hhh]”j )”}”(hhh]”(j)”}”(hŒ?: 'A' if the path is active, 'F' if the path is failed.”h]”(j)”}”(hŒ :”h]”hŒ :”…””}”(hjÛh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K#hj×ubj')”}”(hhh]”hÌ)”}”(hŒ5'A' if the path is active, 'F' if the path is failed.”h]”hŒ=‘A’ if the path is active, ‘F’ if the path is failed.”…””}”(hjìh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K$hjéubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hj×ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K#hjÔubj)”}”(hŒ*: The number of path failures.”h]”(j)”}”(hŒ :”h]”hŒ :”…””}”(hj h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K%hjubj')”}”(hhh]”hÌ)”}”(hŒThe number of path failures.”h]”hŒThe number of path failures.”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K&hjubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hjubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K%hjÔubj)”}”(hŒ9: The size of in-flight I/Os on the path.”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hj9h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K'hj5ubj')”}”(hhh]”hÌ)”}”(hŒ'The size of in-flight I/Os on the path.”h]”hŒ'The size of in-flight I/Os on the path.”…””}”(hjJh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K(hjGubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hj5ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K'hjÔubj)”}”(hŒe: The relative throughput value of the path among all paths in the path-group. ”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hjhh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K,hjdubj')”}”(hhh]”hÌ)”}”(hŒLThe relative throughput value of the path among all paths in the path-group.”h]”hŒLThe relative throughput value of the path among all paths in the path-group.”…””}”(hjyh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K*hjvubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hjdubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K,hjÔubeh}”(h]”h ]”h"]”h$]”h&]”uh1j hjÑubah}”(h]”h ]”h"]”h$]”h&]”uh1j&hj¿ubeh}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K,hj¼ubah}”(h]”h ]”h"]”h$]”h&]”uh1j hj¸ubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K"hh·h²hubh¶)”}”(hhh]”(h»)”}”(hŒ Algorithm”h]”hŒ Algorithm”…””}”(hj´h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhj±h²hh³hÊh´K/ubhÌ)”}”(hŒÍdm-service-time adds the I/O size to 'in-flight-size' when the I/O is dispatched and subtracts when completed. Basically, dm-service-time selects a path having minimum service time which is calculated by::”h]”hŒÐdm-service-time adds the I/O size to ‘in-flight-size’ when the I/O is dispatched and subtracts when completed. Basically, dm-service-time selects a path having minimum service time which is calculated by:”…””}”(hjÂh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K1hj±h²hubhŒ literal_block”“”)”}”(hŒB('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'”h]”hŒB('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'”…””}”hjÒsbah}”(h]”h ]”h"]”h$]”h&]”Œ xml:space”Œpreserve”uh1jÐh³hÊh´K6hj±h²hubhÌ)”}”(hŒYHowever, some optimizations below are used to reduce the calculation as much as possible.”h]”hŒYHowever, some optimizations below are used to reduce the calculation as much as possible.”…””}”(hjâh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K8hj±h²hubj)”}”(hX1. If the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'. 2. If the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'. 3. If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'. ”h]”hŒenumerated_list”“”)”}”(hhh]”(hŒ list_item”“”)”}”(hŒkIf the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'. ”h]”hÌ)”}”(hŒjIf the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'.”h]”hŒrIf the paths have the same ‘relative_throughput’, skip the division and just compare the ‘in-flight-size’.”…””}”(hjÿh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K;hjûubah}”(h]”h ]”h"]”h$]”h&]”uh1jùhjöubjú)”}”(hŒkIf the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'. ”h]”hÌ)”}”(hŒjIf the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'.”h]”hŒrIf the paths have the same ‘in-flight-size’, skip the division and just compare the ‘relative_throughput’.”…””}”(hjh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K>hjubah}”(h]”h ]”h"]”h$]”h&]”uh1jùhjöubjú)”}”(hŒ’If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'. ”h]”hÌ)”}”(hŒ‘If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'.”h]”hŒIf some paths have non-zero ‘relative_throughput’ and others have zero ‘relative_throughput’, ignore those paths with zero ‘relative_throughput’.”…””}”(hj/h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KAhj+ubah}”(h]”h ]”h"]”h$]”h&]”uh1jùhjöubeh}”(h]”h ]”h"]”h$]”h&]”Œenumtype”Œarabic”Œprefix”hŒsuffix”Œ.”uh1jôhjðubah}”(h]”h ]”h"]”h$]”h&]”uh1jh³hÊh´K;hj±h²hubhÌ)”}”(hŒãIf such optimizations can't be applied, calculate service time, and compare service time. If calculated service time is equal, the path having maximum 'relative_throughput' may be better. So compare 'relative_throughput' then.”h]”hŒíIf such optimizations can’t be applied, calculate service time, and compare service time. If calculated service time is equal, the path having maximum ‘relative_throughput’ may be better. So compare ‘relative_throughput’ then.”…””}”(hjTh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KEhj±h²hubeh}”(h]”Œ algorithm”ah ]”h"]”Œ algorithm”ah$]”h&]”uh1hµhh·h²hh³hÊh´K/ubh¶)”}”(hhh]”(h»)”}”(hŒExamples”h]”hŒExamples”…””}”(hjmh²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hºhjjh²hh³hÊh´KMubhÌ)”}”(hŒÀIn case that 2 paths (sda and sdb) are used with repeat_count == 128 and sda has an average throughput 1GB/s and sdb has 4GB/s, 'relative_throughput' value may be '1' for sda and '4' for sdb::”h]”hŒËIn case that 2 paths (sda and sdb) are used with repeat_count == 128 and sda has an average throughput 1GB/s and sdb has 4GB/s, ‘relative_throughput’ value may be ‘1’ for sda and ‘4’ for sdb:”…””}”(hj{h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´KNhjjh²hubjÑ)”}”(hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4”h]”hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4”…””}”hj‰sbah}”(h]”h ]”h"]”h$]”h&]”jàjáuh1jÐh³hÊh´KRhjjh²hubhÌ)”}”(hŒ3Or '2' for sda and '8' for sdb would be also true::”h]”hŒ:Or ‘2’ for sda and ‘8’ for sdb would be also true:”…””}”(hj—h²hh³Nh´Nubah}”(h]”h ]”h"]”h$]”h&]”uh1hËh³hÊh´K\hjjh²hubjÑ)”}”(hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8”h]”hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8”…””}”hj¥sbah}”(h]”h ]”h"]”h$]”h&]”jàjáuh1jÐh³hÊh´K^hjjh²hubeh}”(h]”Œexamples”ah ]”h"]”Œexamples”ah$]”h&]”uh1hµhh·h²hh³hÊh´KMubeh}”(h]”Œdm-service-time”ah ]”h"]”Œdm-service-time”ah$]”h&]”uh1hµhhh²hh³hÊh´Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”hÊuh1hŒcurrent_source”NŒ current_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(hºNŒ generator”NŒ datestamp”NŒ source_link”NŒ source_url”NŒ toc_backlinks”Œentry”Œfootnote_backlinks”KŒ sectnum_xform”KŒstrip_comments”NŒstrip_elements_with_classes”NŒ strip_classes”NŒ report_level”KŒ halt_level”KŒexit_status_level”KŒdebug”NŒwarning_stream”NŒ traceback”ˆŒinput_encoding”Œ utf-8-sig”Œinput_encoding_error_handler”Œstrict”Œoutput_encoding”Œutf-8”Œoutput_encoding_error_handler”jæŒerror_encoding”Œutf-8”Œerror_encoding_error_handler”Œbackslashreplace”Œ language_code”Œen”Œrecord_dependencies”NŒconfig”NŒ id_prefix”hŒauto_id_prefix”Œid”Œ dump_settings”NŒdump_internals”NŒdump_transforms”NŒdump_pseudo_xml”NŒexpose_internals”NŒstrict_visitor”NŒ_disable_config”NŒ_source”hÊŒ _destination”NŒ _config_files”]”Œ7/var/lib/git/docbuild/linux/Documentation/docutils.conf”aŒfile_insertion_enabled”ˆŒ raw_enabled”KŒline_length_limit”M'Œpep_references”NŒ pep_base_url”Œhttps://peps.python.org/”Œpep_file_url_template”Œpep-%04d”Œrfc_references”NŒ rfc_base_url”Œ&https://datatracker.ietf.org/doc/html/”Œ tab_width”KŒtrim_footnote_reference_space”‰Œsyntax_highlight”Œlong”Œ smart_quotes”ˆŒsmartquotes_locales”]”Œcharacter_level_inline_markup”‰Œdoctitle_xform”‰Œ docinfo_xform”KŒsectsubtitle_xform”‰Œ image_loading”Œlink”Œembed_stylesheet”‰Œcloak_email_addresses”ˆŒsection_self_link”‰Œenv”NubŒreporter”NŒindirect_targets”]”Œsubstitution_defs”}”Œsubstitution_names”}”Œrefnames”}”Œrefids”}”Œnameids”}”(jÀj½jgjdj¸jµuŒ nametypes”}”(jÀ‰jg‰j¸‰uh}”(j½h·jdj±jµjjuŒ footnote_refs”}”Œ citation_refs”}”Œ autofootnotes”]”Œautofootnote_refs”]”Œsymbol_footnotes”]”Œsymbol_footnote_refs”]”Œ footnotes”]”Œ citations”]”Œautofootnote_start”KŒsymbol_footnote_start”KŒ id_counter”Œ collections”ŒCounter”“”}”…”R”Œparse_messages”]”Œtransform_messages”]”Œ transformer”NŒ include_log”]”Œ decoration”Nh²hub.