From b895ba18156a5dd0895bf990cb8cc99ed3be007d Mon Sep 17 00:00:00 2001 From: Ciro Santilli Date: Thu, 22 Feb 2018 11:47:01 +0000 Subject: [PATCH 1/2] Document that GEM5 snapshot is better than QEMU since guest started --- README.adoc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/README.adoc b/README.adoc index c9035d5..cd866e5 100644 --- a/README.adoc +++ b/README.adoc @@ -1329,7 +1329,7 @@ I have also tried to copy the exact same kernel command line options used by QEM ===== GEM5 checkpoint -Analogous to QEMU's <>. +Analogous to QEMU's <>, but better since it can be started from inside the guest, so we can easily checkpoint after a specific guest event, e.g. just before `init` is done. Documentation: http://gem5.org/Checkpoints From ecdded0316013a0aef28a3146f337b88cadebb2a Mon Sep 17 00:00:00 2001 From: Ciro Santilli Date: Thu, 22 Feb 2018 15:46:59 +0000 Subject: [PATCH 2/2] gem5 vs qemu license --- README.adoc | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/README.adoc b/README.adoc index cd866e5..69f3f78 100644 --- a/README.adoc +++ b/README.adoc @@ -1180,11 +1180,9 @@ in which the boot appears to hang for a considerable time. === GEM5 -==== GEM5 Introduction - GEM5 is a system simulator, much like QEMU: http://gem5.org/ -Vs QEMU: +==== GEM5 vs QEMU * advantage: simulates a generic more realistic pipelined and optionally out of order CPU cycle by cycle, including a realistic DRAM memory access model with latencies, caches and page table manipulations. This allows us to: ** do much more realistic performance benchmarking with it, which makes absolutely no sense in QEMU, which is purely functional @@ -1201,6 +1199,11 @@ Instead, we have only chip makers, who keep everything that really works closed, + ** the documentation is more scarce ** it takes longer to support new hardware features +* not sure: GEM5 has BSD license while QEMU has GPL ++ +This suits chip makers that want to distribute forks with secret IP to their customers. ++ +On the other hand, the chip makers tend to upstream less, and the project becomes more crappy in average :-) ==== GEM5 ARM