Linux 4.20 – linux kernel newbies gas tracker

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When systems are overcommitted and resources become contended, it’s hard to tell exactly the impact this 9gag instagram logo has on workload productivity, or how close the system is to lockups and OOM kills. In particular, when machines work multiple jobs concurrently, the impact of overcommit in terms of latency and throughput on the individual job can be enormous. In order to maximize hardware utilization without sacrificing individual job health or risk complete machine lockups, this release adds pressure stall information, a way to quantify resource pressure in the system.

Under /proc/pressure/ (and also inside each cgroup), several files expose the percentage of time the system is stalled on CPU, memory, or IO, respectively. These percentages of walltime can be thought of as pressure percentages, and they give electricity 2pm mp3 a general sense of system health and productivity loss incurred by resource overcommit. They can also indicate when the system is approaching lockup scenarios and OOMs.

This release includes udmabuf, a device that can turn memfd regions into dma-buf. It allows qemu to create dmabufs for the vga framebuffer or virtio-gpu resources. Then they can be passed around to display those guest things on the host. To spice client for classic full framebuffer display, and hopefully some day to wayland server for seamless guest window display.

As TLB flushes are extremely expensive, a technique called lazy TLB is employed by Linux which avoids unnecessary TLB flushes by processes gas quality comparison which do not access the userspace page tables as the kernel portion of the address space is always visible. This release tries to use lazy TLB used even lazier: On most workloads, the number of context switches far exceeds the number of TLB flushes sent. Optimizing the context switches, by always using lazy TLB mode, speeds up those workloads. This reduces total CPU use in the system by about 1-2% for a memcache workload on two socket systems, and by about 1% for a heavily multi-process netperf between two systems.

XArray (recommended LWN article The XArray data structure) commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit gas explosion, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit

Introduce kmalloc-reclaimable caches which can be reclaimed under memory pressure (typically through a shrinker), these are shown as kmalloc-rcl-SIZE in /proc/slabinfo. This makes the slab pages accounted gas meter in spanish as NR_SLAB_RECLAIMABLE in vmstat, which is reflected also the MemAvailable counter in /proc/meminfo and in overcommit decisions. A new KReclaimable counter is added to that file show the sum of all reclaimable kernel allocations, including slab. The NR_INDIRECTLY_RECLAIMABLE_BYTES counter is repurposed commit, commit, commit, commit, commit, commit astrid y gaston lima menu english

perf trace: Introduce perf trace –max-events for stopping ‘perf trace’ when that many syscalls (enter+exit), tracepoints or other events such as page faults take place. Support that as well on a per-event basis, e.g.: perf trace -e sched:*switch/nr=2/,block:*_plug/nr=4/,block:*_unplug/nr=1/,net:*dev_queue/nr=3,max-stack=16/ Will stop when 2 context switches, 4 block plugs, 1 block electricity cost in california unplug and 3 net_dev_queue tracepoints take place commit, commit, commit, commit

Support TPM-wrapped key and crypto ops. This adds 1) keyctl() functions that permit an asymmetric-type key to be used to encrypt, decrypt, sign and verify a small piece of data using the public and/or private key held in the kernel 2) an asymmetric-key parser for PKCS#8 to allow RSA private keys to be passed to the kernel 3) an asymmetric-key parser for TPM-wrapped key blobs commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit

Implement kernel filtering of route dumps by protocol (e.g., which routing daemon installed the route), route type (e.g., unicast), table id and nexthop device. iproute2 has been doing this filtering in userspace for years; pushing the filters gas in babies to the kernel side improves efficiency on large scale systems commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit

NXP i.MX usually sees a lot of new boards each release. This time there we only add one minor variant: ConnectCore 6UL SBC Pro commit uses the same SoM design as the ConnectCore 6UL SBC Express added later. However, there is a new chip, the i.MX6ULZ, which is an even smaller variant of the i.MX6ULL, with features removed. There is also support for the reference board design electricity physics, the i.MX6ULZ 14×14 EVK commit, commit

On the Allwinner side, everything is again about cheap development boards, usually of the Fruit Pi variety. The new ones this time are: Orange Pi Zero Plus2 commit, Orange Pi One Plus commit, Pine64 LTS commit, Banana Pi M2+ H5 commit, commit. The last one of these is now a 64-bit version of the earlier Banana Pi M2+ H3, with the same board layout.

For Rockchips, we get another variant of the 32-bit Asus Tinker board e payment electricity bill maharashtra, the model ‘S’ based on rk3288 commit, and three now boards based on the popular RK3399 chip: ROC-RK3399-PC commit, Rock960 commit, RockPro64 commit. These are all quite powerful boards with lots of RAM and I/O, and the RK3399 is the same chip used in several Chromebooks. Finally, we get support for the PX30 (aka rk3326) chip, which is based on the low-end 64-bit Cortex-A35 CPU core. So far, only the evaluation board is supported commit, commit

(FEATURED) Make lazy TLB mode even lazier: On most workloads, the number of context switches far exceeds the number of TLB flushes sent. Optimizing the context switches, by always using lazy TLB mode, speeds up those workloads. This results in about a 1% reduction in CPU use on a two socket Broadwell system running a memcache like workload commit, commit, commit, commit, commit, commit, commit

Add a new per-VM capability ( KVM_CAP_EXCEPTION_PAYLOAD) will be introduced. When this gas stoichiometry lab capability is enabled by userspace, the faulting linear address will be included with the information about a pending eur j gastroenterology hepatology impact factor #PF in L2, and the new DR6 bits will be included with the information about a pending #DB in L2. This ancillary exception information is carried in a new payload field commit, commit, commit, commit, commit, commit, commit

Add a new driver for Marvell’s OcteonTX2 SOC’s Resource virtualization unit (RVU) admin function driver commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit, commit