{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/73097"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/73097","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"High quality functional coverage based trace signal selection for post-silicon validation","abstract":"Due to the drastic growth of design complexity and also shrinkage of the time-to-market window, it is always impossible to capture all bugs during the pre-silicon verification phase; therefore, a small number of bugs escape after a chip is manufactured. Once a chip is manufactured, it is considered as a black box since internal observability is lost. To increase observability for post-silicon validation, an effective silicon debug technique is to use an on-chip trace buffer to monitor and capture the circuit response of certain selected signals during its post-silicon operation. Since this aforementioned debugging trace buffer introduces area overhead, the amount of signals selected to be stored on this trace buffer is very limited. Therefore, a major challenge in this field is to select a powerful subset of internal signals to reconstruct the majority of the remaining signal values. Existing methods use a greedy selection process to converge to a locally optimal selection; this kind of method suffers from severe diminishing restoration ratio effect as more trace signals are selected. In addition, all of the previous publications have been focused on increasing restorability; none of them has ever been able to interpret the trace signals as high level meaningful debugging information. In this thesis, we formulate the trace signal selection problem into a data-mining problem and propose two approaches using PageRank and HITS algorithm. Our experimental results demonstrate that our algorithm can effectively alleviate the diminishing restoration ratio effect. Furthermore, we propose a new metric to evaluate the quality of selected trace signals instead of restorability, which is the number of functionalities they cover when debugging; this is an angle previous publications have not addressed. According to our experimental results, the two new algorithms proposed in this thesis select better and more meaningful trace signals in terms of debugging.","abstract_html":"Due to the drastic growth of design complexity and also shrinkage of the time-to-market window, it is always impossible to capture all bugs during the pre-silicon verification phase; therefore, a small number of bugs escape after a chip is manufactured. Once a chip is manufactured, it is considered as a black box since internal observability is lost. To increase observability for post-silicon validation, an effective silicon debug technique is to use an on-chip trace buffer to monitor and capture the circuit response of certain selected signals during its post-silicon operation. Since this aforementioned debugging trace buffer introduces area overhead, the amount of signals selected to be stored on this trace buffer is very limited. Therefore, a major challenge in this field is to select a powerful subset of internal signals to reconstruct the majority of the remaining signal values. Existing methods use a greedy selection process to converge to a locally optimal selection; this kind of method suffers from severe diminishing restoration ratio effect as more trace signals are selected. In addition, all of the previous publications have been focused on increasing restorability; none of them has ever been able to interpret the trace signals as high level meaningful debugging information. In this thesis, we formulate the trace signal selection problem into a data-mining problem and propose two approaches using PageRank and HITS algorithm. Our experimental results demonstrate that our algorithm can effectively alleviate the diminishing restoration ratio effect. Furthermore, we propose a new metric to evaluate the quality of selected trace signals instead of restorability, which is the number of functionalities they cover when debugging; this is an angle previous publications have not addressed. According to our experimental results, the two new algorithms proposed in this thesis select better and more meaningful trace signals in terms of debugging.","abstract_has_math":false,"creators":["Ma, Sai"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Electrical & Computer Engr","degree_department":null,"school":null,"contributors":["Vasudevan, Shobha"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-01-21T19:59:29Z","date_published":"2015-01-21T19:59:29Z","updated_at":"2026-07-22T22:26:07Z","subjects":["Post-silicon validation","Signal tracing","PageRank"],"languages":["en"],"rights":["Copyright 2014 Sai Ma"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/73097","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Vasudevan, Shobha"]},{"key":"dc:creator","label":"Author","values":["Ma, Sai"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2015-01-21T19:59:29Z","2017-01-22T10:15:29Z","2014-12","2015-01-21"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical & Computer Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Post-silicon validation","Signal tracing","PageRank"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2014 Sai Ma"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/73097"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Due to the drastic growth of design complexity and also shrinkage of the time-to-market window, it is always impossible to capture all bugs during the pre-silicon verification phase; therefore, a small number of bugs escape after a chip is manufactured. Once a chip is manufactured, it is considered as a black box since internal observability is lost. To increase observability for post-silicon validation, an effective silicon debug technique is to use an on-chip trace buffer to monitor and capture the circuit response of certain selected signals during its post-silicon operation. Since this aforementioned debugging trace buffer introduces area overhead, the amount of signals selected to be stored on this trace buffer is very limited. Therefore, a major challenge in this field is to select a powerful subset of internal signals to reconstruct the majority of the remaining signal values. Existing methods use a greedy selection process to converge to a locally optimal selection; this kind of method suffers from severe diminishing restoration ratio effect as more trace signals are selected. In addition, all of the previous publications have been focused on increasing restorability; none of them has ever been able to interpret the trace signals as high level meaningful debugging information. In this thesis, we formulate the trace signal selection problem into a data-mining problem and propose two approaches using PageRank and HITS algorithm. Our experimental results demonstrate that our algorithm can effectively alleviate the diminishing restoration ratio effect. Furthermore, we propose a new metric to evaluate the quality of selected trace signals instead of restorability, which is the number of functionalities they cover when debugging; this is an angle previous publications have not addressed. According to our experimental results, the two new algorithms proposed in this thesis select better and more meaningful trace signals in terms of debugging.","Item withdrawn by Laura Spradlin (lspradl2@illinois.edu) on 2014-12-10T14:12:33Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Ma_Sai.pdf: 3975510 bytes, checksum: bfe6d51b4f364a794c9ac29e9d9d07c9 (MD5)","Made available in DSpace on 2015-01-21T19:59:29Z (GMT). No. of bitstreams: 1 Sai_Ma.pdf: 3975510 bytes, checksum: bfe6d51b4f364a794c9ac29e9d9d07c9 (MD5)","Embargo set by: Seth Robbins for item 73286 Lift date: 2017-01-21T19:59:39Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Limited Restriction Lifted for Item 73286 on 2017-01-22T10:15:29Z."]},{"key":"dc:title","label":"Title","values":["High quality functional coverage based trace signal selection for post-silicon validation"]}]}],"canonical_facts":{"dc:contributor":["Vasudevan, Shobha"],"dc:creator":["Ma, Sai"],"dc:date":["2015-01-21T19:59:29Z","2017-01-22T10:15:29Z","2014-12","2015-01-21"],"dc:description":["Due to the drastic growth of design complexity and also shrinkage of the time-to-market window, it is always impossible to capture all bugs during the pre-silicon verification phase; therefore, a small number of bugs escape after a chip is manufactured. Once a chip is manufactured, it is considered as a black box since internal observability is lost. To increase observability for post-silicon validation, an effective silicon debug technique is to use an on-chip trace buffer to monitor and capture the circuit response of certain selected signals during its post-silicon operation. Since this aforementioned debugging trace buffer introduces area overhead, the amount of signals selected to be stored on this trace buffer is very limited. Therefore, a major challenge in this field is to select a powerful subset of internal signals to reconstruct the majority of the remaining signal values. Existing methods use a greedy selection process to converge to a locally optimal selection; this kind of method suffers from severe diminishing restoration ratio effect as more trace signals are selected. In addition, all of the previous publications have been focused on increasing restorability; none of them has ever been able to interpret the trace signals as high level meaningful debugging information. In this thesis, we formulate the trace signal selection problem into a data-mining problem and propose two approaches using PageRank and HITS algorithm. Our experimental results demonstrate that our algorithm can effectively alleviate the diminishing restoration ratio effect. Furthermore, we propose a new metric to evaluate the quality of selected trace signals instead of restorability, which is the number of functionalities they cover when debugging; this is an angle previous publications have not addressed. According to our experimental results, the two new algorithms proposed in this thesis select better and more meaningful trace signals in terms of debugging.","Item withdrawn by Laura Spradlin (lspradl2@illinois.edu) on 2014-12-10T14:12:33Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Ma_Sai.pdf: 3975510 bytes, checksum: bfe6d51b4f364a794c9ac29e9d9d07c9 (MD5)","Made available in DSpace on 2015-01-21T19:59:29Z (GMT). No. of bitstreams: 1 Sai_Ma.pdf: 3975510 bytes, checksum: bfe6d51b4f364a794c9ac29e9d9d07c9 (MD5)","Embargo set by: Seth Robbins for item 73286 Lift date: 2017-01-21T19:59:39Z Reason: Author requested closed access (OA after 2yrs) in Vireo ETD system","Limited Restriction Lifted for Item 73286 on 2017-01-22T10:15:29Z."],"dc:identifier":["http://hdl.handle.net/2142/73097"],"dc:language":["en"],"dc:rights":["Copyright 2014 Sai Ma"],"dc:subject":["Post-silicon validation","Signal tracing","PageRank"],"dc:title":["High quality functional coverage based trace signal selection for post-silicon validation"],"dc:type":["text"],"thesis:degree_discipline":["Electrical & Computer Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:26:07Z"}