caching

问题 Hi everyone I want to implement cache map in java in which map entries expire after given time. I have interface like this, I have to implement these methods, but I am not understand how actually start. public class CacheMapImpl implements CacheMap<Integer, String> { @Override public void setTimeToLive(long timeToLive) { } @Override public long getTimeToLive() { return 0; } @Override public String put(Integer key, String value) { return null; } @Override public void clearExpired() { }

问题 Hi everyone I want to implement cache map in java in which map entries expire after given time. I have interface like this, I have to implement these methods, but I am not understand how actually start. public class CacheMapImpl implements CacheMap<Integer, String> { @Override public void setTimeToLive(long timeToLive) { } @Override public long getTimeToLive() { return 0; } @Override public String put(Integer key, String value) { return null; } @Override public void clearExpired() { }

问题 I'm trying to speed up a matrix multiplication algorithm by blocking the loops to improve cache performance, yet the non-blocked version remains significantly faster regardless of matrix size, block size (I've tried lots of values between 2 and 200, potenses of 2 and others) and optimization level. Non-blocked version: for(size_t i = 0; i < n; ++i) { for(size_t k = 0; k < n; ++k) { int r = a[i][k]; for(size_t j = 0; j < n; ++j) { c[i][j] += r * b[k][j]; } } } Blocked version: for(size_t kk =

问题 I want to do block matrix-matrix multiplication with the following C code.In this approach, blocks of size BLOCK_SIZE is loaded into the fastest cache in order to reduce memory traffic during calculation. void bMMikj(double **A , double **B , double ** C , int m, int n , int p , int BLOCK_SIZE){ int i, j , jj, k , kk ; register double jjTempMin = 0.0 , kkTempMin = 0.0; for (jj=0; jj<n; jj+= BLOCK_SIZE) { jjTempMin = min(jj+ BLOCK_SIZE,n); for (kk=0; kk<n; kk+= BLOCK_SIZE) { kkTempMin = min(kk

问题 I want to do block matrix-matrix multiplication with the following C code.In this approach, blocks of size BLOCK_SIZE is loaded into the fastest cache in order to reduce memory traffic during calculation. void bMMikj(double **A , double **B , double ** C , int m, int n , int p , int BLOCK_SIZE){ int i, j , jj, k , kk ; register double jjTempMin = 0.0 , kkTempMin = 0.0; for (jj=0; jj<n; jj+= BLOCK_SIZE) { jjTempMin = min(jj+ BLOCK_SIZE,n); for (kk=0; kk<n; kk+= BLOCK_SIZE) { kkTempMin = min(kk

问题 I have a simple ASP.NET Core 2.2 Web Api controller: [ApiVersion("1.0")] [Route("api/[controller]")] [ApiController] public class TestScenariosController : Controller { [HttpGet("v2")] public ActionResult<List<TestScenarioItem>> GetAll() { var entities = _dbContext.TestScenarios.AsNoTracking().Select(e => new TestScenarioItem { Id = e.Id, Name = e.Name, Description = e.Description, }).ToList(); return entities; } } When I query this action from angular app using @angular/common/http : this

问题 From what I've read, the "volatile" keyword in java ensures that a thread always fetches the most up-to-date value of a particular pointer, usually by reading/writing directly from/to memory to avoid cache inconsistencies. But why is this needed? To my knowledge, this is already done on a hardware level. If I remember correctly from my system architecture class, A processor-core that updates a memory location, sends an invalidation signal to the other processor's caches, forcing them to fetch

问题 From what I've read, the "volatile" keyword in java ensures that a thread always fetches the most up-to-date value of a particular pointer, usually by reading/writing directly from/to memory to avoid cache inconsistencies. But why is this needed? To my knowledge, this is already done on a hardware level. If I remember correctly from my system architecture class, A processor-core that updates a memory location, sends an invalidation signal to the other processor's caches, forcing them to fetch

问题 From what I've read, the "volatile" keyword in java ensures that a thread always fetches the most up-to-date value of a particular pointer, usually by reading/writing directly from/to memory to avoid cache inconsistencies. But why is this needed? To my knowledge, this is already done on a hardware level. If I remember correctly from my system architecture class, A processor-core that updates a memory location, sends an invalidation signal to the other processor's caches, forcing them to fetch

问题 I have been sitting here for almost an hour here to test the website I'm building. Since I wanted to see the new changes from my code I reloaded, but it was reloading old one. I opened the devetools to hard reload and empy cache hard reload, they both load my old code. I went to incognito mode and it did the same thing. I went to devtools again to disable the cache from the settings and checked the disable cache in the network tab; it still cache my old code. Add-ons to clear the cache didn't