Ojo Fragmentado MinecraftUS response to Zika: Fragmented and uneven. On Sept. 1, officials in Florida reported that mosquitoes carrying the Zika virus had been found in Miami Beach. The Florida Department of Health reports 4. Zika. There are almost 2,7. U. S. Things are worse in the U. S. The Centers for Disease Control and Prevention is doing what it can to support efforts to halt disease transmission and support state and local government. But on August 3. 0 CDC Director Tom Frieden announced that the agency had almost run out of money to fight the virus. It was my belief some people like my son Joshua and myself have “fragmented thinking” which is akin to sitting behind a pole at a ball game. The AIIB Is a Threat to Global Economic Governance. The era of a U.S.-dominated global economic order is ending. But a fragmented governance system isn't the best. Cortes Generales = Congreso de los Diputados + Senado. Cortes Generales es el nombre oficial del Parlamento espa Home Forums Facebook Twitter Reddit FAQ Support. Home Forums Facebook Twitter Reddit FAQ Support. Panasonic Viera UHD TV review: good hardware, fragmented software Great picture quality let down by bipolar software, leaving this TV wanting for smarts. Congress has yet to pass a funding bill, leaving the Obama administration to redirect money earmarked for other purposes to support Zika research and response efforts. The response so far seem fragmented, and even somewhat contentious. We can look back to the Ebola crisis in the U. S. As my colleague Phillip Singer and I found in a case study, the response to that public health crisis was shaped by the fragmented and partisan U. S. A map showing the active Zika zone is on display at the Borinquen Health Care Center in Miami, Florida, on August 9, 2. Chris Keane/File Photo/Reuters. How does public health in the U. S. Local public health policy is mostly overseen, created and funded at the state level. And public health work from disease surveillance to health education to mosquito abatement is done by local governments and nonprofits that work with them. These include safety net health care facilities, mosquito abatement agencies (whose very presence is patchy), social services agencies and so on. However, public health at the state and local level is often underfunded. If disease threats seem more distant, state and local governments may assume that there will be no threats or that the federal government will help them out if something does happen. Recessions are especially likely to lead to reduced funding in areas like clinics for the poor or mosquito abatement. When a crisis does happen, the responses within individual states tend to be driven by governors, who will often take guidance from the federal government. However, we found that national political ambitions can influence how governors react. They can choose to show leadership, or challenge the president, in ways that aid their own ambitions. For instance, New Jersey Governor Chris Christie tried to quarantine a nurse who had returned from work in West Africa, while Louisiana Governor Bobby Jindal threatened to quarantine any members of The American Society of Tropical Medicine and Hygiene who tried to attend their conference in New Orleans after working in affected countries. Both men announced presidential bids within the following year. Formally, a wide variety of local governments under the aegis of states. But because public health in the U. S. For instance, within a week of the CDC releasing guidance for monitoring people with potential exposure to Ebola in the U. S., all 5. 0 states, as well as New York City and Washington, D. C., had implemented them. While politicians like Christie or Jindal can choose to defy federal advice, most prefer to fall into line. With Zika, states have already been working with the federal government to think through their responses. And as we learned in our case study of Ebola, public health works through persuasion rather than hierarchy. For example, the White House. Federal money can also support disease control efforts on the ground, and compensate for the fact the local public health is underfunded. So, it poses a problem when the federal government isn. Which, right now, it isn. By early February 2. White House sent a proposal to Congress for US$1. US territories such as Puerto Rico, expand Zika testing in the United States and support research on a vaccine. About $4. 00 million was earmarked to fight the disease abroad. The House and Senate responded with bills of their of own. The Senate bill cut the allocation and would have put Ebola funds toward Zika response. The House bill offered one- third of the funding the administration requested. While Congress stalemated, the Obama administration transferred almost $6. Ebola funds, to fight Zika. In August, the Obama administration used its administrative flexibility to move $8. Ebola response and other health programs to keep a Zika vaccine study going and support to the local governments. These executive actions reduced the pressure on Congress to act by funding Zika response and vaccine research, even if only shoestring budget. And because Congress hasn. And now the CDC, which has been supporting Zika response efforts (including giving money to partners organizations to support local, state, territorial and tribal efforts), is running out of the money that the administration reallocated from other uses to combat the virus. Will Zika funding pass before November 8? Pressure is mounting on Congress to act. Three- quarters of the public in a Kaiser Family Foundation survey think it is an issue that needs to be addressed when Congress returns from recess on Sept. Florida Republicans including Marco Rubio and Governor Rick Scott have already started to attack Washington. Democrats, including President Obama, continue to attack Republicans in Congress over the slowness of the response. Fear of Zika might start to overcome partisanship, but there is no guarantee that will happen before Nov. Before the elections, politicians, especially Republicans who hoped to make gains in Congress, linked it to immigration and border security, emphasized biological threats and attacked the executive branch. Looking at Washington might make us glad that all does not depend on federal politics. But that is not so comforting when we consider the funding and capacity of local and state governments in the areas, particularly along the Gulf Coast, that are most endangered. This spring Miami- Dade County had a mosquito control staff of 1. It is now under a domestic travel advisory. Fragmentation (computing) - Wikipedia. In computer storage, fragmentation is a phenomenon in which storage space is used inefficiently, reducing capacity or performance and often both. The exact consequences of fragmentation depend on the specific system of storage allocation in use and the particular form of fragmentation. In many cases, fragmentation leads to storage space being . For other systems (e. Fragmentation is often accepted in return for improvements in speed or simplicity. Analogous phenomena occur for other resources such as processors; see below. Basic principle. When the computer program is finished with a chunk, it can free the chunk back to the system, making it available to later be allocated again to another or the same program. The size and the amount of time a chunk is held by a program varies. During its lifespan, a computer program can request and free many chunks of memory. When a program is started, the free memory areas are long and contiguous. Over time and with use, the long contiguous regions become fragmented into smaller and smaller contiguous areas. Eventually, it may become impossible for the program to obtain large contiguous chunks of memory. Types of fragmentation. For example, memory can only be provided to programs in chunks divisible by 4, 8 or 1. When this happens, the excess memory goes to waste. In this scenario, the unusable memory is contained within an allocated region. This arrangement, termed fixed partitions, suffers from inefficient memory use - any process, no matter how small, occupies an entire partition. This waste is called internal fragmentation. For example, in dynamic memory allocation, memory pools drastically cut internal fragmentation by spreading the space overhead over a larger number of objects. External fragmentation. It is a weakness of certain storage allocation algorithms, when they fail to order memory used by programs efficiently. The result is that, although free storage is available, it is effectively unusable because it is divided into pieces that are too small individually to satisfy the demands of the application. The memory allocator can use this free block of memory for future allocations. However, it cannot use this block if the memory to be allocated is larger in size than this free block. External fragmentation also occurs in file systems as many files of different sizes are created, change size, and are deleted. The effect is even worse if a file which is divided into many small pieces is deleted, because this leaves similarly small regions of free spaces. Comments. Start with all memory available for allocation. ABCAllocated three blocks A, B, and C, of size 0x. ACFreed block B. Notice that the memory that B used cannot be included for an allocation larger than B's size. Data fragmentation. It is typically the result of attempting to insert a large object into storage that has already suffered external fragmentation. For example, files in a file system are usually managed in units called blocks or clusters. When a file system is created, there is free space to store file blocks together contiguously. This allows for rapid sequential file reads and writes. However, as files are added, removed, and changed in size, the free space becomes externally fragmented, leaving only small holes in which to place new data. When a new file is written, or when an existing file is extended, the operating system puts the new data in new non- contiguous data blocks to fit into the available holes. The new data blocks are necessarily scattered, slowing access due to seek time and rotational latency of the read/write head, and incurring additional overhead to manage additional locations. This is called file system fragmentation. When writing a new file of a known size, if there are any empty holes that are larger than that file, the operating system can avoid data fragmentation by putting the file into any one of those holes. There are a variety of algorithms for selecting which of those potential holes to put the file; each of them is a heuristic approximate solution to the bin packing problem. For example, the primary job of a defragmentation tool is to rearrange blocks on disk so that the blocks of each file are contiguous. Most defragmenting utilities also attempt to reduce or eliminate free space fragmentation. Some moving garbage collectors will also move related objects close together (this is called compacting) to improve cache performance. There are 4 kinds of systems that never experience data fragmentation. All 4 kinds have significant disadvantages compared to systems that allow at least some temporary data fragmentation: Simply write each file contiguously, as with CD- R. If there isn't already enough contiguous free space to hold the file, the system immediately fails to store the file. This takes a lot more time than breaking the file up into fragments and putting those fragments into the available free space. If a programmer picks a fixed block size too small, the system immediately fails to store some files. If a programmer picks a block size too big, we waste a lot of space on internal fragmentation. Some systems avoid dynamic allocation entirely, pre- allocating (contiguous) space for all possible files they will need. It is defined as: External Memory Fragmentation=1. Therefore, if a highly fragmented file or many small files are deleted from a full volume and then a new file with size equal to the newly freed space is created, the new file will simply reuse the same fragments that were freed by the deletion. If what was deleted was one file, the new file and will be just as fragmented as that old file was, but in any case there will be no barrier to using all the (highly fragmented) free space to create the new file. In RAM, on the other hand, the allocation systems used often cannot assemble a large block to meet a request from small noncontiguous free blocks, and so the request cannot be fulfilled and the program cannot proceed to do whatever it needed that memory for (unless it can reissue the request as a number of smaller separate requests). Problems. Fragmentation causes this to occur even if there is enough of the resource, but not a contiguous amount. For example, if a computer has 4 Gi. B of memory and 2 Gi. B are free, but the memory is fragmented in an alternating sequence of 1 Mi. B used, 1 Mi. B free, then a request for 1 contiguous Gi. B of memory cannot be satisfied even though 2 Gi. B total are free. In order to avoid this, the allocator may, instead of failing, trigger a defragmentation (or memory compaction cycle) or other resource reclamation, such as a major garbage collection cycle, in the hope that it will then be able to satisfy the request. This allows the process to proceed, but can severely impact performance. Performance degradation. Most basically, fragmentation increases the work required to allocate and access a resource. For example, on a hard drive or tape drive, sequential data reads are very fast, but seeking to a different address is slow, so reading or writing a fragmented file requires numerous seeks and is thus much slower, in addition to causes greater wear on the device. Further, if a resource is not fragmented, allocation requests can simply be satisfied by returning a single block from the start of the free area. However it is fragmented, the request requires either searching for a large enough free block, which may take a long time, or fulfilling the request by several smaller blocks (if this is possible), which results in this allocation being fragmented, and requiring additional overhead to manage the several pieces. A subtler problem is that fragmentation may prematurely exhaust a cache, causing thrashing, due to caches holding blocks, not individual data. For example, suppose a program has a working set of 2. Ki. B, and is running on a computer with a 2. Ki. B cache (say L2 instruction+data cache), so the entire working set fits in cache and thus executes quickly, at least in terms of cache hits. Suppose further that it has 6. TLB) entries, each for a 4 Ki. B page: each memory access requires a virtual- to- physical translation, which is fast if the page is in cache (here TLB). If the working set is unfragmented, then it will fit onto exactly 6. However, if the working set is fragmented, then it will not fit into 6. TLB during operation. Thus cache sizing in system design must include margin to account for fragmentation. Memory fragmentation is one of the most severe problems faced by system managers. Eventually, memory fragmentation may lead to complete loss of (application- usable) free memory. Memory fragmentation is a kernelprogramming level problem. During real- time computing of applications, fragmentation levels can reach as high as 9. However, while it may not be possible for a system to continue running all programs in the case of excessive memory fragmentation, a well- designed system should be able to recover from the critical fragmentation condition by moving in memory some memory blocks used by the system itself in order to enable consolidation of free memory into fewer, larger blocks, or, in the worst case, by terminating some programs to free their memory and then defragmenting the resulting sum total of free memory. This will at least avoid a true crash in the sense of system failure and allow the system to continue running some programs, save program data, etc. It is also important to note that fragmentation is a phenomenon of system software design; different software will be susceptible to fragmentation to different degrees, and it is possible to design a system that will never be forced to shut down or kill processes as a result of memory fragmentation. Analogous phenomena. More fundamentally, time- sharing itself causes external fragmentation of processes due to running them in fragmented time slices, rather than in a single unbroken run.
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