308:. The reason was claimed to be inherent in the operating-system structure imposed by microkernels. Liedtke, however, observed that the message-passing operation (IPC), which is fundamentally important for microkernel performance, was slow in all existing microkernels, including his own L3 system. His conclusion was that radical redesign was needed. He did this by re-implementing L3 from scratch, dramatically simplifying the kernel, resulting in an order-of-magnitude decrease in IPC cost. The resulting kernel was later renamed "L4". Conceptually, the main novelty of L4 was its complete reliance on external pagers (
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357:. There, he continued to collaborate with IBM on Saw Mill, but at the same time worked on a new generation of L4 (version 4). Several experimental kernels were developed during that time, including Hazelnut, the first L4 kernel that was ported (in contrast to re-implemented) to a different architecture (from
295:
interpreter he had written in high school). L3 was designed to achieve better performance by using the latest hardware features, and was implemented from scratch. It was mostly backward-compatible with Eumel, thus benefiting from the existing Eumel ecosystem. L3 started to ship in 1989, with total
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systems, a popular design in the 1980s. However, by the early 1990s, microkernels had received a bad reputation, as systems built on top were performing poorly, culminating in the billion-dollar failure of the
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504:. Proceedings of the Fourteenth ACM Symposium on Operating Systems Principles. SOSP '93. New York, NY, USA: Association for Computing Machinery (ACM). pp. 175–188.
342:, where he continued to work on L4, referred to as “Lava Nucleus” (LN) to avoid negative connotations with previously unsuccessful microkernels, such as the one used in
547:. Proceedings of the Fifteenth ACM Symposium on Operating Systems Principles. SOSP '95. New York, NY, USA: Association for Computing Machinery (ACM). pp. 237–250.
1812:
598:. Proceedings of the Fifteenth ACM Symposium on Operating Systems Principles. SOSP'01. New York, NY, USA: Association for Computing Machinery (ACM). pp. iii.
384:, having been ill earlier in the year and undergone two surgeries (the conference proceedings were dedicated to his memory). He is survived by his wife Adelheid.
365:). Work on the new version was completed after his death by Liedtke's students Volkmar Uhlig, Uwe Dannowski, and Espen Skoglund. It was released under the name
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which added the features missing from the hardware. More than 2000 Eumel systems shipped, mostly to schools, and some to legal practices as a
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Proceedings of the 3rd
International Workshop on Object Orientation in Operating Systems (IWOOOS)
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After his graduation in 1977, he remained at
Bielefeld and worked on an Elan environment for the
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407:(December 1993). "A persistent system in real use—experiences of the first 13 years".
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handlers), and the recursive construction of address spaces. This led to a complete
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In the mid-1970s
Liedtke studied for a diploma degree in mathematics at the
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address space. In 1996, Liedtke completed a PhD on guarded page tables at
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In April 1999, he took up the System
Architecture Chair at the
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438:. Asheville, North Carolina, United States. pp. 120–133.
242:, which started shipping () in 1980 and was later ported to
411:. Asheville, North Carolina, United States. pp. 2–11.
234:). Eumel grew into a complete multi-tasking, multi-user
577:"Page Table Structures for Fine-Grain Virtual Memory"
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372:On Sunday June 10, 2001, he died unexpectedly at
270:Gesellschaft fĂĽr Mathematik und Datenverarbeitung
430:Chen, Bradley; Bershad, Brian (December 1993).
452:(September 1996). "Toward Real Microkernels".
1756:Category: Microkernel-based operating systems
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291:("Liedtke's 3rd system", after Eumel and the
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283:became widely available in the form of the
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623:In Memoriam Jochen Liedtke (1953 - 2001)
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7:
1813:Technische Universität Berlin alumni
202:. His thesis project was to build a
350:into an L4-based multi-server OS.
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589:Marzullo, Keith (December 2001).
380:'01 program committee meeting in
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340:Thomas J. Watson Research Center
222:microprocessor. This required a
142:Thomas J. Watson Research Center
338:In the same year he joined the
628:List of Liedtke's publications
502:Improving IPC by Kernel Design
226:(environment), which he named
1:
333:Technische Universität Berlin
206:for the programming language
181:, especially in creating the
93:Technische Universität Berlin
1803:Computer systems researchers
296:deployment of at least 500.
1010:Multi-Environment Real-Time
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1798:German computer scientists
417:10.1109/IWOOOS.1993.324932
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454:Communications of the ACM
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592:Operating Systems Review
541:On ÎĽ-Kernel Construction
174:, noted for his work on
630:related to microkernels
355:University of Karlsruhe
319:Liedtke also worked on
299:Both Eumel and L3 were
265:In 1984, he joined the
146:University of Karlsruhe
1766:Category: Microkernels
314:family of microkernels
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240:orthogonal persistence
553:10.1145/224056.224075
511:10.1145/168619.168633
476:10.1145/234215.234473
376:while returning from
321:computer architecture
183:L4 microkernel family
1745:Open-source software
1252:Java virtual machine
323:, inventing guarded
200:Bielefeld University
89:Bielefeld University
1704:Andrew S. Tanenbaum
382:Chateau Lake Louise
1808:Kernel programmers
277:Fraunhofer Society
172:computer scientist
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1674:Per Brinch Hansen
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538:(December 1995).
500:(December 1993).
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179:operating systems
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1265:
1259:
1232:
1199:
1184:
1177:
1170:
1157:
1146:
1140:
1134:
1094:Nucleus RTOS
1079:
1062:
1055:
1043:
1024:
1018:
1014:
1008:
1000:
973:
966:
953:
913:
894:
887:
877:
864:
848:
837:
829:
821:
806:
787:
765:
759:
739:
732:
700:
694:
665:Microkernels
591:
584:
571:
540:
535:
530:
501:
497:
492:
460:(9): 70–77.
457:
453:
449:
444:
435:
425:
408:
404:
371:
366:
352:
344:Workplace OS
337:
318:
298:
266:
264:
217:
197:
167:
166:
134:Institutions
113:
70:(2001-06-10)
68:10 June 2001
18:
1793:2001 deaths
1788:1953 births
1654:Gordon Bell
1544:OpenComRTOS
1441:Singularity
1267:Chorus/Jazz
1190:OpenHarmony
669:nanokernels
325:page tables
301:microkernel
285:Intel 80386
244:Zilog Z8000
238:supporting
176:microkernel
77:Nationality
50:26 May 1953
1782:Categories
1646:Developers
1613:Frameworks
1550:Phantom OS
1514:ChibiOS/RT
872:µ-velOSity
866:MicroEmpix
388:References
310:page fault
262:platform.
252:Intel 8086
46:1953-05-26
1737:Real-time
1694:Ike Nassi
1669:Dan Dodge
1433:Microsoft
1303:Unix-like
1293:Macintosh
1201:HarmonyOS
1088:Integrity
987:Minix-vmd
947:Unix-like
926:Operating
724:Macintosh
462:CiteSeerX
369:in 2002.
367:Pistachio
220:Zilog Z80
214:Post grad
194:Education
1520:FreeRTOS
1477:Taligent
1409:Broadway
1403:AspireOS
1273:ChorusOS
1194:Oniro OS
1081:ChorusOS
961:GNU Hurd
915:Vanguard
857:GNU Mach
741:NuKernel
293:ALGOL 60
204:compiler
1727:Italics
1636:TI-RTOS
1584:Harmony
1563:SharpOS
1557:RC 4000
1526:HelenOS
1446:ThreadX
1423:MorphOS
1392:AmigaOS
1371:Symbian
1348:kernel)
1346:PowerPC
1334:Copland
1319:MacMach
1312:MachTen
1073:Partial
1019:Unix-RT
1002:MkLinux
993:Minix 3
939:support
928:systems
902:RTLinux
896:PowerUP
879:nucleus
677:Kernels
484:2867357
58:Germany
54:Herford
1630:Genode
1624:Cosmos
1602:Zephyr
1507:BeRTOS
1499:Amoeba
1295:hosted
1261:JavaOS
1241:Wombat
1234:REX OS
1227:PikeOS
1221:LLinux
1214:kernel
1172:Midori
1153:CapROS
1142:KeyKOS
1136:GNOSIS
1057:UNICOS
1045:Spring
1026:OS2000
975:MeikOS
808:WarpOS
795:ExecSG
726:hosted
688:family
602:
559:
518:
482:
464:
329:64-bit
189:Career
120:Fields
80:German
1578:Thoth
1532:µC/OS
1453:Verve
1385:-type
1383:Amiga
1357:Psion
1179:NLTSS
1159:Hydra
1100:NuttX
1051:Tinix
1038:Redox
981:Minix
968:Lites
937:POSIX
823:ADEOS
802:Quark
781:-type
779:Amiga
752:Psion
696:Eumel
596:(PDF)
545:(PDF)
480:S2CID
348:Linux
228:Eumel
1743:° =
1735:^ =
1617:kits
1596:VRTX
1587:^ →
1581:^ →
1570:SPIN
1472:Pink
1397:AROS
1365:EPOC
1165:seL4
1148:EROS
1112:RIOT
1064:VSTa
1015:MERT
889:Opus
850:Mach
831:EROS
789:Exec
767:EKA2
761:EKA1
713:OKL4
600:ISBN
557:ISBN
516:ISBN
378:SOSP
250:and
208:ELAN
65:Died
40:Born
1538:MQX
1106:OSE
1032:QNX
1013:^ (
955:ARX
839:K42
549:doi
506:doi
472:doi
413:doi
363:ARM
361:to
359:x86
138:GMD
1784::
1638:^°
1615:,
1604:^°
1552:^°
1534:^°
1522:^°
1516:^°
1510:^°
1481:→
1479:OS
1474:→
1399:°
1375:^°
1373:OS
1368:→
1281:JX
1276:^)
1243:^°
1223:^°
1212:L4
1198:→
1192:,
1167:^°
1151:→
1145:→
1139:→
1114:^°
1102:^°
1017:–
983:°
910:^°
853:°
834:^°
770:^°
764:→
707:L4
705:→
702:L3
699:→
686:L4
555:.
514:.
478:.
470:.
458:39
456:.
434:.
396:^
335:.
289:L3
246:,
185:.
105:,
103:L3
56:,
1632:°
1626:°
1598:^
1590:V
1573:°
1565:°
1546:^
1540:^
1528:°
1502:°
1448:^
1417:°
1411:°
1405:°
1344:(
1284:°
1264:(
1237:^
1229:^
1196:)
1188:(
1108:^
1096:^
1090:^
1083:^
1040:°
1034:^
1021:)
1005:°
995:°
989:°
963:°
904:°
874:^
859:°
842:°
826:°
715:°
709:°
667:-
657:e
650:t
643:v
608:.
565:.
551::
524:.
508::
486:.
474::
419:.
415::
48:)
44:(
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
