€•½JŒsphinx.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]”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”…””}”(hh¨hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hh£hžhhŸŒW/var/lib/git/docbuild/linux/Documentation/admin-guide/device-mapper/dm-service-time.rst”h KubhŒ paragraph”“”)”}”(hŒ˜dm-service-time is a path selector module for device-mapper targets, which selects a path with the shortest estimated service time for the incoming I/O.”h]”hŒ˜dm-service-time is a path selector module for device-mapper targets, which selects a path with the shortest estimated service time for the incoming I/O.”…””}”(hh¹hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(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.”…””}”(hhÇhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hh£hžhubh¸)”}”(hŒ)The path selector name is 'service-time'.”h]”hŒ-The path selector name is ‘service-time’.”…””}”(hhÕhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubh¸)”}”(hŒTable parameters for each path:”h]”hŒTable parameters for each path:”…””}”(hhãhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khh£hžhubhŒ block_quote”“”)”}”(hXÊ[ []] : The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table. : The relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available. ”h]”hŒdefinition_list”“”)”}”(hhh]”hŒdefinition_list_item”“”)”}”(hXš[ []] : The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table. : The relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available. ”h]”(hŒterm”“”)”}”(hŒ([ []]”h]”hŒ([ []]”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h KhhþubhŒ definition”“”)”}”(hhh]”hø)”}”(hhh]”(hý)”}”(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:”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h Khjubj)”}”(hhh]”h¸)”}”(hŒ·The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table.”h]”hŒ·The number of I/Os to dispatch using the selected path before switching to the next path. If not given, internal default is used. To check the default value, see the activated table.”…””}”(hj/hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj,ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h Khjubhý)”}”(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:”…””}”(hjMhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h KhjIubj)”}”(hhh]”h¸)”}”(hŒñThe relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value '1' is used. If '0' is given, the path isn't selected while other paths having a positive value are available.”h]”hŒûThe relative throughput value of the path among all paths in the path-group. The valid range is 0-100. If not given, minimum value ‘1’ is used. If ‘0’ is given, the path isn’t selected while other paths having a positive value are available.”…””}”(hj^hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h Khj[ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjIubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h Khjubeh}”(h]”h ]”h"]”h$]”h&]”uh1h÷hjubah}”(h]”h ]”h"]”h$]”h&]”uh1jhhþubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h Khhùubah}”(h]”h ]”h"]”h$]”h&]”uh1h÷hhóubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhŸh¶h Khh£hžhubh¸)”}”(hŒStatus for each path:”h]”hŒStatus for each path:”…””}”(hj–hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K hh£hžhubhò)”}”(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]”hø)”}”(hhh]”hý)”}”(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< ”…””}”(hj¯hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h K,hj«ubj)”}”(hhh]”hø)”}”(hhh]”(hý)”}”(hŒ?: 'A' if the path is active, 'F' if the path is failed.”h]”(j)”}”(hŒ :”h]”hŒ :”…””}”(hjÇhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h K#hjÃubj)”}”(hhh]”h¸)”}”(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.”…””}”(hjØhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K$hjÕubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjÃubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h K#hjÀubhý)”}”(hŒ*: The number of path failures.”h]”(j)”}”(hŒ :”h]”hŒ :”…””}”(hjöhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h K%hjòubj)”}”(hhh]”h¸)”}”(hŒThe number of path failures.”h]”hŒThe number of path failures.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K&hjubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjòubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h K%hjÀubhý)”}”(hŒ9: The size of in-flight I/Os on the path.”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hj%hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h K'hj!ubj)”}”(hhh]”h¸)”}”(hŒ'The size of in-flight I/Os on the path.”h]”hŒ'The size of in-flight I/Os on the path.”…””}”(hj6hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K(hj3ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhj!ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h K'hjÀubhý)”}”(hŒe: The relative throughput value of the path among all paths in the path-group. ”h]”(j)”}”(hŒ:”h]”hŒ:”…””}”(hjThžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1jhŸh¶h K,hjPubj)”}”(hhh]”h¸)”}”(hŒLThe relative throughput value of the path among all paths in the path-group.”h]”hŒLThe relative throughput value of the path among all paths in the path-group.”…””}”(hjehžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K*hjbubah}”(h]”h ]”h"]”h$]”h&]”uh1jhjPubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h K,hjÀubeh}”(h]”h ]”h"]”h$]”h&]”uh1h÷hj½ubah}”(h]”h ]”h"]”h$]”h&]”uh1jhj«ubeh}”(h]”h ]”h"]”h$]”h&]”uh1hühŸh¶h K,hj¨ubah}”(h]”h ]”h"]”h$]”h&]”uh1h÷hj¤ubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhŸh¶h K"hh£hžhubh¢)”}”(hhh]”(h§)”}”(hŒ Algorithm”h]”hŒ Algorithm”…””}”(hj hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjhžhhŸh¶h K/ubh¸)”}”(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:”…””}”(hj®hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K1hjhžhubhŒ literal_block”“”)”}”(hŒB('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'”h]”hŒB('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'”…””}”hj¾sbah}”(h]”h ]”h"]”h$]”h&]”Œ xml:space”Œpreserve”uh1j¼hŸh¶h K6hjhžhubh¸)”}”(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.”…””}”(hjÎhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K8hjhžhubhò)”}”(hX1. If the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'. 2. If the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'. 3. If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'. ”h]”hŒenumerated_list”“”)”}”(hhh]”(hŒ list_item”“”)”}”(hŒkIf the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'. ”h]”h¸)”}”(hŒjIf the paths have the same 'relative_throughput', skip the division and just compare the 'in-flight-size'.”h]”hŒrIf the paths have the same ‘relative_throughput’, skip the division and just compare the ‘in-flight-size’.”…””}”(hjëhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K;hjçubah}”(h]”h ]”h"]”h$]”h&]”uh1jåhjâubjæ)”}”(hŒkIf the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'. ”h]”h¸)”}”(hŒjIf the paths have the same 'in-flight-size', skip the division and just compare the 'relative_throughput'.”h]”hŒrIf the paths have the same ‘in-flight-size’, skip the division and just compare the ‘relative_throughput’.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K>hjÿubah}”(h]”h ]”h"]”h$]”h&]”uh1jåhjâubjæ)”}”(hŒ’If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'. ”h]”h¸)”}”(hŒ‘If some paths have non-zero 'relative_throughput' and others have zero 'relative_throughput', ignore those paths with zero 'relative_throughput'.”h]”hŒIf some paths have non-zero ‘relative_throughput’ and others have zero ‘relative_throughput’, ignore those paths with zero ‘relative_throughput’.”…””}”(hjhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KAhjubah}”(h]”h ]”h"]”h$]”h&]”uh1jåhjâubeh}”(h]”h ]”h"]”h$]”h&]”Œenumtype”Œarabic”Œprefix”hŒsuffix”Œ.”uh1jàhjÜubah}”(h]”h ]”h"]”h$]”h&]”uh1hñhŸh¶h K;hjhžhubh¸)”}”(hŒãIf such optimizations can't be applied, calculate service time, and compare service time. If calculated service time is equal, the path having maximum 'relative_throughput' may be better. So compare 'relative_throughput' then.”h]”hŒíIf such optimizations can’t be applied, calculate service time, and compare service time. If calculated service time is equal, the path having maximum ‘relative_throughput’ may be better. So compare ‘relative_throughput’ then.”…””}”(hj@hžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KEhjhžhubeh}”(h]”Œ algorithm”ah ]”h"]”Œ algorithm”ah$]”h&]”uh1h¡hh£hžhhŸh¶h K/ubh¢)”}”(hhh]”(h§)”}”(hŒExamples”h]”hŒExamples”…””}”(hjYhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h¦hjVhžhhŸh¶h KMubh¸)”}”(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:”…””}”(hjghžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h KNhjVhžhubj½)”}”(hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4”h]”hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4”…””}”hjusbah}”(h]”h ]”h"]”h$]”h&]”jÌjÍuh1j¼hŸh¶h KRhjVhžhubh¸)”}”(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:”…””}”(hjƒhžhhŸNh Nubah}”(h]”h ]”h"]”h$]”h&]”uh1h·hŸh¶h K\hjVhžhubj½)”}”(hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8”h]”hX # echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \ dmsetup create test # # dmsetup table test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8 # # dmsetup status test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8”…””}”hj‘sbah}”(h]”h ]”h"]”h$]”h&]”jÌjÍuh1j¼hŸh¶h K^hjVhžhubeh}”(h]”Œexamples”ah ]”h"]”Œexamples”ah$]”h&]”uh1h¡hh£hžhhŸh¶h KMubeh}”(h]”Œdm-service-time”ah ]”h"]”Œdm-service-time”ah$]”h&]”uh1h¡hhhžhhŸh¶h Kubeh}”(h]”h ]”h"]”h$]”h&]”Œsource”h¶uh1hŒcurrent_source”NŒ current_line”NŒsettings”Œdocutils.frontend”ŒValues”“”)”}”(h¦NŒ 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”jÒŒerror_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”h¶Œ _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”}”(j¬j©jSjPj¤j¡uŒ nametypes”}”(j¬‰jS‰j¤‰uh}”(j©h£jPjj¡jVuŒ 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”Nhžhub.