{"id":1208,"date":"2019-09-06T15:15:00","date_gmt":"2019-09-06T13:15:00","guid":{"rendered":"https:\/\/samovar2022.int-evry.fr\/index.php\/2019\/09\/06\/seminaire-methodes-presente-par-alexandre-brandwajn-le-26-09-2019-a-10h30-en-a03-a-telecom-sudparis\/"},"modified":"2020-09-04T18:45:18","modified_gmt":"2020-09-04T16:45:18","slug":"seminaire-methodes-presente-par-alexandre-brandwajn-le-26-09-2019-a-10h30-en-a03-a-telecom-sudparis","status":"publish","type":"post","link":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/2019\/09\/06\/seminaire-methodes-presente-par-alexandre-brandwajn-le-26-09-2019-a-10h30-en-a03-a-telecom-sudparis\/","title":{"rendered":"S\u00e9minaire Methodes pr\u00e9sent\u00e9 par Alexandre Brandwajn le 26\/09\/2019  \u00e0 10h30 en A03 \u00e0 T\u00e9l\u00e9com SudParis"},"content":{"rendered":"<p>Le laboratoire Samovar accueille M. Alexandre Brandwajn ( Computer Engineering, UCSC, USA) pour une pr\u00e9sentation intitul\u00e9e \u00ab\u00a0Multi-server preemptive priority queue with general arrivals and service times\u00a0\u00bb<\/p>\n<p><strong>Quand:<\/strong> Le Jeudi 26 septembre 2019, \u00e0 10h30<br \/>\n<strong>O\u00f9:<\/strong> En salle A03, \u00e0 T\u00e9l\u00e9com SudParis, Evry<\/p>\n<p><strong>Titre: <\/strong> Multi-server preemptive priority queue with general arrivals and service times<br \/>\nAlexandre Brandwajn, Computer Engineering, UCSC, USA<br \/>\n(joint work with Thomas Begin, ENS-Lyon, France)<\/p>\n<p><strong>Abstract :<\/strong><br \/>\nWe present a simple approximate solution for preemptive-resume queues with multiple servers, general service and inter-arrival time distributions.  In our solution, we solve priority levels one at a time in the order of decreasing priorities. We solve each priority level approximately using a reduced state description.  The complexity of our approximate solution in terms of the number of equations solved grows linearly with the number of servers and priority levels.<br \/>\nNumerical results from a large number of examples indicate that, overall, in the case of Poisson and quasi-Poisson arrivals, expected relative error for the mean number of customers in the system tends to be below 2% while the corresponding median relative error stays below 0.25%.  The good accuracy of our approximation appears to extend to the case of general times between arrivals, with expected relative errors for the mean number in system below 5% even for a Pareto-like distribution of inter-arrival times with a large coefficient of variation.  Thus, the proposed approximation provides a relatively simple and generally accurate approach to preemptive-resume queues with larger numbers of servers and general distributions of service and inter-arrival times.<\/p>\n<p><img decoding=\"async\" class=\" alignleft size-full wp-image-1207\" src=\"https:\/\/samovar2022.int-evry.fr\/wp-content\/uploads\/2019\/09\/a.brandwajn.jpg\" alt=\"a.brandwajn.jpg\" align=\"left\" width=\"129\" height=\"177\" \/><\/p>\n<p><strong>Brief biography<\/strong><br \/>\nAlexandre Brandwajn holds a Ing\u00e9nieur Civil des T\u00e9l\u00e9communications degree from the Ecole Nationale Sup\u00e9reure des T\u00e9l\u00e9communications in Pairs, and a Docteur d\u2019Etat in Computer Science degree from the University of Paris VI. He worked as researcher at the Institut de Recherche en Informatique et Automatique (IRIA), France; then, he was on the faculty of the Ecole Nationale Superieure des Telecommunications in Paris where he directed a project in adaptive computer architecture. Later he joined Amdahl Corporation in Sunnyvale, California, where he was a senior computer architect, and then manager of Systems Analysis group. Since 1985, he is a professor of Computer Engineering at the University of California at Santa Cruz and President of PALLAS International Corporation in the SF Bay Area. His current research interests include efficient solution of systems with large state space, application of conditional probability in the solution of performance models, models of virtualized systems, and efficient solution of priority systems.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Le laboratoire Samovar accueille M. Alexandre Brandwajn ( Computer Engineering, UCSC, USA) pour une pr\u00e9sentation intitul\u00e9e \u00ab\u00a0Multi-server preemptive priority queue with general arrivals and service times\u00a0\u00bb Quand: Le Jeudi 26 septembre 2019, \u00e0 10h30 O\u00f9: En salle A03, \u00e0 T\u00e9l\u00e9com SudParis, Evry Titre: Multi-server preemptive priority queue with general arrivals and service times Alexandre Brandwajn, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1207,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"ocean_post_layout":"","ocean_both_sidebars_style":"","ocean_both_sidebars_content_width":0,"ocean_both_sidebars_sidebars_width":0,"ocean_sidebar":"","ocean_second_sidebar":"","ocean_disable_margins":"enable","ocean_add_body_class":"","ocean_shortcode_before_top_bar":"","ocean_shortcode_after_top_bar":"","ocean_shortcode_before_header":"","ocean_shortcode_after_header":"","ocean_has_shortcode":"","ocean_shortcode_after_title":"","ocean_shortcode_before_footer_widgets":"","ocean_shortcode_after_footer_widgets":"","ocean_shortcode_before_footer_bottom":"","ocean_shortcode_after_footer_bottom":"","ocean_display_top_bar":"default","ocean_display_header":"default","ocean_header_style":"","ocean_center_header_left_menu":"","ocean_custom_header_template":"","ocean_custom_logo":0,"ocean_custom_retina_logo":0,"ocean_custom_logo_max_width":0,"ocean_custom_logo_tablet_max_width":0,"ocean_custom_logo_mobile_max_width":0,"ocean_custom_logo_max_height":0,"ocean_custom_logo_tablet_max_height":0,"ocean_custom_logo_mobile_max_height":0,"ocean_header_custom_menu":"","ocean_menu_typo_font_family":"","ocean_menu_typo_font_subset":"","ocean_menu_typo_font_size":0,"ocean_menu_typo_font_size_tablet":0,"ocean_menu_typo_font_size_mobile":0,"ocean_menu_typo_font_size_unit":"px","ocean_menu_typo_font_weight":"","ocean_menu_typo_font_weight_tablet":"","ocean_menu_typo_font_weight_mobile":"","ocean_menu_typo_transform":"","ocean_menu_typo_transform_tablet":"","ocean_menu_typo_transform_mobile":"","ocean_menu_typo_line_height":0,"ocean_menu_typo_line_height_tablet":0,"ocean_menu_typo_line_height_mobile":0,"ocean_menu_typo_line_height_unit":"","ocean_menu_typo_spacing":0,"ocean_menu_typo_spacing_tablet":0,"ocean_menu_typo_spacing_mobile":0,"ocean_menu_typo_spacing_unit":"","ocean_menu_link_color":"","ocean_menu_link_color_hover":"","ocean_menu_link_color_active":"","ocean_menu_link_background":"","ocean_menu_link_hover_background":"","ocean_menu_link_active_background":"","ocean_menu_social_links_bg":"","ocean_menu_social_hover_links_bg":"","ocean_menu_social_links_color":"","ocean_menu_social_hover_links_color":"","ocean_disable_title":"default","ocean_disable_heading":"default","ocean_post_title":"","ocean_post_subheading":"","ocean_post_title_style":"","ocean_post_title_background_color":"","ocean_post_title_background":0,"ocean_post_title_bg_image_position":"","ocean_post_title_bg_image_attachment":"","ocean_post_title_bg_image_repeat":"","ocean_post_title_bg_image_size":"","ocean_post_title_height":0,"ocean_post_title_bg_overlay":0.5,"ocean_post_title_bg_overlay_color":"","ocean_disable_breadcrumbs":"default","ocean_breadcrumbs_color":"","ocean_breadcrumbs_separator_color":"","ocean_breadcrumbs_links_color":"","ocean_breadcrumbs_links_hover_color":"","ocean_display_footer_widgets":"default","ocean_display_footer_bottom":"default","ocean_custom_footer_template":"","ocean_post_oembed":"","ocean_post_self_hosted_media":"","ocean_post_video_embed":"","ocean_link_format":"","ocean_link_format_target":"self","ocean_quote_format":"","ocean_quote_format_link":"post","ocean_gallery_link_images":"on","ocean_gallery_id":[],"footnotes":""},"categories":[288],"tags":[],"class_list":["post-1208","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-seminaires-2020-methodes-fr","entry","has-media"],"_links":{"self":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/1208","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/comments?post=1208"}],"version-history":[{"count":1,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/1208\/revisions"}],"predecessor-version":[{"id":1449,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/posts\/1208\/revisions\/1449"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/media\/1207"}],"wp:attachment":[{"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/media?parent=1208"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/categories?post=1208"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/samovar.telecom-sudparis.eu\/index.php\/wp-json\/wp\/v2\/tags?post=1208"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}