以 -X 开头的参数是和实现有关的，并不是适用于所有的 VMs，对于 -Xms 和 -Xmx 其含义为：. client or server, see -client and -server parameters) and on your system memory. The -Xms has a lot to do with frame performance. -XX:PermSize: -XX:MaxPermSize: are used to set size for Permanent Generation. Simplified: "-Xmx4G -Xms4G" = 4GB of memory allocated to Minecraft. When this parameter is not tuned, you may see some performance implications (for example, large spikes in the memory foot print). 2. Então dei uma pesquisada e estou compartilhando oque eu aprendi. There's a "Game Specific" section in the column on the left side of the settings page. Keep -Xms Small. However, the -Xms option can be used with all GC policies except for the metronome GC policy because the heap is always fully expanded. Attachments. . If you want to force Minecraft to use that amount of memory, you should use -Xms instead of -Xmx. See Using -X command-line options for more information about the <size> parameter. If the value of the -Xms parameter is smaller than the value of the -Xmx parameter, than not all of the space that is reserved is immediately committed to the virtual machine. 8GB of RAM is, in most cases, enough for a "default". So when you set -Xmx and -Xms, you will get a portion of virtual memory allocated as needed. 2) For HOW TO, enter the procedure in steps. Scroll down to "Java Settings" where you'll see "Allocated Memory" with a slider. Therefore a value like -Xms128m will set the minimum heap size to 128 MB. And they just work fine. Use -XX:MaxRAMPercentage / -XX:InitialRAMPercentage instead. 物理内存的1/4 (<1GB) 默认 (MaxHeapFreeRatio参数可以调整)空余堆内存大于70%时，JVM会减少堆直到 -Xms的最小限制. Sort By Name; Sort By Date;La configuración de los parámetros está empaquetada. Xmn is well, I'm not an expert in terms of flags so IBM's answer will be all I can say. This avoids the JVM to be constantly increasing the heap and can gain some performance. That's what you need to change. . Xmn、Xms、Xmx、Xss都是JVM对内存的配置参数，我们可以根据不同需要区修改这些参数，以达到运行程序的最好效果。. Short answer: All memory sizes used by the JVM command line arguments are specified in the traditional binary units, where a kilobyte is 1024 bytes, and the others are increasing powers of 1024. and testing -Xmx and -Xmn $ . defaultAction openFile --launcher. This option was. Quote. 0_29 on Windows 7/32-bit: -Xmx256m -XX:MaxPermSize=64m. client or server, see -client and -server parameters) and on your system memory. Older区的大小等于-Xmx减去-Xmn,不能将-Xms的值设的过大,因为第二个线程被迫运行会降低JVM的性能. Due to various additional constraints such as available swap, kernel address space usage, memory fragmentation, and VM overhead, in practice the limit can be much lower. For a reference on what settings to use for your system try installing the JDK (instead of just the JRE) and running jconsole. The Java/JVM Xms and Xmx settings should both pre-allocate the amount of memory to start along with the maximum defined value to designate to the Java/JVM instance. how severely "should" we. For example, you can set the Java heap size to 258 MB by running the following command: java -Xmx256m HelloWord. By doing so, it may assist to. java -XX:+PrintFlagsFinal -version | grep HeapSize. Estes parâmetros são passados em linha de comando. e. 如果程序运行需要占用更多的内存，超出了这个设置值. This would allow the game to use up to 4 gigs of ram and start with 1 gig of ram when your launch minecraft. You should: Enable Full GC logging. Nota: Lo simplificamos como memoria máxima y mínima aunque es un poco más complejo que esto, tiene que ver con el heap de Java. Another option is to set -Xms to the memory-usage value observed at the end of InitServlet. Error: Could not create the Java Virtual Machine. -Xms. "(select your class and open the Arguments tab put it in the VM arguments area) menu, and NOT on Eclipse startup. thank you man you just helped me alot. As such, these numbers being the same is not necessary and sometimes not a good idea. 0_65"，Java HotSpot(TM) Client VM，Client VM要比Server VM的默认值小. Xmx 是指设定程序运行期间最大可占用的内存大小。. The Java heap can never grow larger than -Xmx. -Xmx 堆内存的最大大小，默认为物理内存的1/4. Your Xms and Xmx should probably. Get JAVA_OPTS Environment Variable in Java. The Xms flag tells to your JVM the amount of memory for initial allocation. Anyways, it doesn't use much more ram. etc. The next time you start Minecraft it will use the settings specified in the . Edit: details you asked for. Maximum size of the permanent generation. Syntax. . Xms is the minimum memory to allocate to the program and Xmx is the maximum it is allowed to grow to. If you apply an advanced option, you always precede the option with -XX:. Just one snapshot of Generation size is not enough. 8GB of RAM is, in most cases, enough for a "default" Server with not like 100 plugins and many many players. JVM参数 -Xms 和 -Xmx 是用来设置Java虚拟机（JVM）堆的初始大小和最大大小的。. Oracle recomienda que -Xmn y -Xmx se establezcan en el mismo valor. jar once, waited for it to compile all the settings, set the EULA as true, and then ran the server again, but this time, it wouldn't let me run the command to specify the RAM (-xms). This is the option that forces Minecraft to use that amount of. im trying to run the server start. You want. check user_args. 8. 5GB. This argument is used to specify the maximum RAM usage by Minecraft on your system. The line below shows 3 JVM arguments. Download Apache Tomcat. 1/4th of the physical memory or 1GB. g. Note that the Max ram you allocate will be unusable by the rest of your system so there is really no point in setting the Min amount lower. ago. Xmx just sets the maximum RAM the Server can use and Xms is the minimum RAM the server gets. First I realised that Xmx was only set to 1G although the server I rent is supposed to have 2G. 减少堆空间调整的频率 ：当-Xmx和-Xms设置为相同的值时，Java虚拟机不需要根据程序的需求动态调整堆空间的大小。. 机器. java -XX:+PrintFlagsFinal -version | findstr HeapSize. There’s also Xms, though. The actual RAM usage will be higher, as java needs some space for itself, for loaded classes, for garbage collection temporary internals, etc. . Format for specifying xms: java -xms{Numerical Size}{Unit} where Unit is k/K for kilobytes, m/M for megabytes, and g/G for gigabytes. There is only a need for graphics processing if the machine in question is also running a client (i. The flag -XX:+UseCGroupMemoryLimitForHeap lets the JVM detect what the max heap size in a container should be. So for a 1G machine maximum heap size is 256MB 2. MaxHeapSize（最大堆大小）就是Xmx的默认值，InitialHeapSize（最小堆大小）时Xms的默认值，默认值和Java的版本有关，像上面的截图Windows中的Xmx默认值是256M，java version "1. 3. Try to increase -Xmx value. -Xmn6144m. Enjoy ad-free music across all genres and decades, news and issues, talk shows and podcasts, comedy, and more. order of the flags doesn't matter, so long as they're before -jar whatever. What to set depend on your application and your hardware. To answer your example, the JVM would reserve 2500M heap space. Syntax. Sets the value of the stop-the-world (STW) worker. Improve this answer. java - xmn - xmx xms minecraft - Code Examples How to Allocate More RAM to Minecraft in Windows 10. As per online description following are properties used in Java linked with Sizes: Use -Xmx to specify the maximum heap size. 0_91"-Xms is the start value of your Java heap size. This heap is always being replenished with new objects. Xmx sets the maximum amount of used RAM, Xms sets the amount of RAM allocated on start. This means that when you start your program the JVM will allocate this amount of memory instantly. jar nogui" command but it wont work, i get a flash of command prompt and nothing else. forge 1. client. The only one, and JVM argument in general (speaking about the default launcher arguments) you should be changing is Xmx, although I still use the older launcher arguments which included Xmn, but only Xmx was changed (and removing CMSIncrementalMode, which is not even supported by newer versions of Java and was otherwise intended for single-core. - xmx3550m : Sets the maximum available memory for the JVM to 3550M. By using the -Xmx switch can be used to change the maximum heap size. By default, the size is in bytes. As a result, while waiting for JAVA to handle memory allocation changes, it can help prevent performance issues. 5G~2G；64为操作系统对内存无限制。. JVMオプションについてのまとめです。. 2. . What to set depend on your application and your hardware. Pause times are independent of heap size that is being used. Proof: Run the application XX:NativeMemoryTracking=summary and check used memory with jcmd VM. /temp/jd. Your -Xms decides the allocated memory your server uses, which will increase automatically when your server needs more ram. bat settings. Use -Xmx to specify the maximum heap size; Use -Xms to specify the initial Java heap size; Use -Xss to set the Java thread stack size; Use this syntax to specify the. -Xms1G will set the MINIMUM HEAP to 1GB at start-up. -Xmx1G -Xms4G This would allow the game to use up to 4 gigs of ram and start with 1. Instead "free" shows only 1 GB is used and 7 GB is free. Xms 是指设定程序启动时占用内存大小。. Many options that are useful for other collectors to respond in some particular way, have either no effect at all,. -Xms ~ -Xmx 값으로 되는 건가 싶네. Some java -Xms -Xmx examples : # Start with 128MB of memory, and allow the Java process to use up to 1024MB of memory. It is also not recommended to set -Xms too high; Notice: You can't give Minecraft more RAM than you have in your system!It varies on implementation and version, but usually it depends on the VM used (e. Pause times are independent of heap size that is being used. These sizes reflect VIRTUAL MEMORY allocations which can be physical mapped to pages in RAM called the RESIDENT SIZE of the process at any time. Xms specifies the initial memory allocation pool on process startup. 0. -Xmx specifies the precise upper limit for the heap. When using the balanced GC policy, specifying -Xmn / -Xmns / -Xmnx may affect balanced GC's ability to satisfy -Xgc:targetPausetime. Correct: java -Xmx1024m -jar JavaApplication. The -xmx option is used to set the final and maximum heap size in Java. Tick the box next to 'JVM Arguements'. Choose Service as Data. The default value is 64MB for a server JVM. You should carefully read the. Rather, it specifies the initial heap size (i. 5GB of ram, because the heap size (Xmx and Xms) isn't the only thing that java allocates. QFdongdong 阅读 399 评论 0 赞 0. 4. Use -XX:MaxRAMPercentage / -XX:InitialRAMPercentage instead. Sets the maximum size of the nursery. 6 GB. วิธีการ เพิ่ม RAM ให้เกม Minecraft. 堆大小设置. java -Xms128m -Xmx1024m. Live & ExclusiveMore than a PlaylistA-List Artists & Hosts. -Xmx - This option sets the maximum Java heap size. If -Xms and -Xmx are the same value, then the JVM's heap size will stay constant at that value. We currently have everything set up to stay within our 1GB guaranteed RAM, but it seems as if we are not. 例如，启动JVM（如下所示）将使用256 MB内存启动，并且允许进程使用最多2048 MB内存：. So here is some details. Instead this parameter overrides the actual amount of physical RAM when calculating the heap limits basing on ergonomics. For example, if you set -Xms128M and -Xmx256M and you start monitoring your application with VisualVM , you'll see something like this:Sorted by: 51. Generally, when I need more memory for Minecraft, I set the max heap and not the min heap. It is just a warning message about another JVM parameter -XX:PermSize which is not supported since Java 8, because Permanent Generation was replaced with Metaspace. -Xms1024m to -Xmx2048m). There is probably a small benefit somewhere in the OS scheduling/reservation realm. 设置堆初始值 方式1: -Xms2g 方式2: -XX:InitialHeapSize=2048m 设置堆最大值 方式1：-Xmx4g 方式2：-XX:MaxHeapSize=4g 动态扩容堆内存，当xmx=xms时无效 -XX:MaxHeapFreeRatio=70 堆内存使用率大于70%时，进行扩张内存 动态缩放堆内存，当xmx=xms时无效 -XX:MinHeapFreeRatio=40. - Committed가 -Xms, MAX가 -Xmx 값인 듯. To further tune your memory usage. -Xmn 堆内新生代. The -Xmx 4G option simply determines the maximum amount of memory that Minecraft can use, it does not mean that Minecraft are forced to use that amount of memory. Share. Select the one you want to change the amount of RAM for, click on the. Does this mean the garbage collector wont activate until the JVM. This documentation page on the command line arguments says the following applies to all the arguments accepting memory sizes:Semana passada visitei a casa da minha vó e tentei jogar minecraft no pc de lá. -Xmn. You can increase or decrease the memory allocated to minecraft by modifying the Xmx and Xms values respectively. The thinking that it does something magical for garbage collection. 3) For FAQ, keep your answer crisp with examples. Xmx is the max memory the game can use while Xms is the starting given amount. For efficient garbage collection, the -Xmn value should be lower than the -Xmx value. -Xmn is an allocated space that the Java GC passes often. These options control the runtime behavior of the Java HotSpot VM. jar. 5GB to Minecraft using the -Xmx Java argument, that amount won't be reserved immediately. Important VM parameters > > Most important and frequently used VM (JVM) PARAMETERS with examples in JVM Heap memory in java > What are -Xms and -Xmx JVM parameters in java, And differences between them with examples >-Xmn JVM parameters in java with examples - Setting young generation size > What is -XX:NewRatio JVM parameters in. 一般来讲，大点，程序会启动的快一点，但是也可能会导致机器暂时间变慢。. If. Hello guys i want to ask about how can i increase the memory usage of the game server. Esto elimina las potencialmente costosas reasignaciones de la pila, y puede reducir la cantidad de fragmentación de la pila que puede ocurrir. e. XMX is the maximum amount of memory that can be allocated. Figure 4-1 illustrates the difference between committed space and virtual space in the heap. This also leaves room for the Operating System to use memory too. If you have 50-70 mods running, then 1 or 2G is enough for minecraft. Also, the -Xms value can be used as “minimum heap size” to set a fixed heap size by setting -Xms = -Xmx. Heap size does not determine the amount of memory your process uses. The resulting output is in bytes. Once the JAVA_OPTS is set, we can get the settings in Java by using the. -Xmx. for example, you can set the java heap size to 258MB by executing following command java -Xmx256m HelloWorld. -Xms Sets the minimum heap size. There are a lot of complicated arguments listed in there but the two to adjust are -Xmx {nn} and -Xms {nn} (-Xmn on Mac's). GuestNo8655 • 2 yr. These are three main categories of Command-Line Argument options: Standard options :Options that begin with - are Standard options are expected to be accepted by all JVM implementations and are stable between releases (though they can be deprecated). Alternatively you can try to switch to G1 garbage collector using -XX:+UseG1GC. You can increase or change the size of the Java heap space using the -Xms, -Xmx, and -Xmn JVM command line option. Default values of heap size parameters on 64-bit systems have been scaled up by approximately 30%. Run: java -X for details. The -Xmx flag set the max heap size to a fixed size. It sounds counterintuitive, but both -XX:MaxRAMPercentage and -XX:MinRAMPercentage are used to calculate maximum heap size when MaxHeapSize / -Xmx is not set:. in my experience the game runs the best without setting -Xms, and if I set it the same as -Xmx then performance is terrible. 如果程序运行需要占用更多的内存，超出了这个设置值，就会抛出OutOfMemory异常。. alla then ktlv gi ayto m dhmiourgithike to pa. There are three types of options that you can add to your JVM, standard, non-standard and advanced options. If you are giving it a full command, give it the -Xms, but if you are simply calling the main class in the jar, then your app needs the -Xms. product --launcher. Minimum java heap size. java内存和linux中内存的关系-xms-xmx无效-xms-xmx无效在查询生产问题时发现-xmx无效，jvm这个进程所产生的内存竟然远-远超出了-xmx，怎么回事？以下是个人的推断，没有去认真学习操作系统的进程管理。在操作系统. Note that -X options are not guaranteed to exist on all VMs or behave the same on all VMs. , how much memory will initially be used when launching. -Xms 参数用来设置JVM堆的初始大小，即在JVM启动时，分配给Java堆的最小内存量。. ・メタスペースの最大値を512MB確保して、それ以上. I have readed that CMSIncrementalMode and Xmn are not usefull, right ? Also, I don't know if I should use -Xms,-XX:ParallelGCThreads, -Dsun. 【提升】遊戲性能真正提升---Xmx 是設定記憶體使用最大值，而-Xms 則是設定成記憶體使用最小值 以一台記憶體有8G 的電腦來說，使用5G ~ 6G 記憶體就已經相當充足 ,回覆. exe -o true . By default, the JVM grows or shrinks the heap at each GC to try to keep the proportion of free space to the living objects at each collection within a specific range. -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC . You should carefully read the logs on. -Xms -Xmn -Xmx. XmnXmsXmxXss有什么区别 Xmn、Xms、Xmx、Xss都是JVM对内存的配置参数，我们可以根据不同需要区修改这些参数，以达到运行程序的最好效果。. The heap size for young generation heap space is Xmn. For testing, you can also set the heap sizes using the ES_JAVA_OPTS environment variable:JVM 参数配置及详解 -Xms -Xmx -Xmn -Xss 调优总结. d/ directory. ) ALL need a bit of memory. I tried Xmx as 3GB (3272 MB) and after that not allowed to define . 3. -Xmx<size>. 系统的可用虚拟内存限制;3. This means that your JVM will be started with Xms amount of memory and will be able to use a maximum of Xmx amount of memory. -Xms is the start value of your Java heap size. -Xms: Sets the minimum and initial size of the heap. Where it says "JVM Arguments" (at the bottom) type in: "-Xmx [amount of memory in GB]G -Xms [same amount of memory in GB]G". 在系. Committed memory becomes resident in a lazy fashion (resident is actual in RAM, for example). The Xms was increased to give the application a healthy start, and Xmx was significantly raised to accommodate the volume of data during peak times. -Xmn is an allocated space that the Java GC passes often. 为什么一些程序频繁发生GC?有如下原因: l 程序内调用了System. JVM. It is the preferred way to set the heap size. Surprisingly yes! This is carried to prevent resizing during startup and enhance the startup time of JVM. It is currently using 80% of a 4GB heap and rising a few percent each day. To allocate more memory to Minecraft, do the following: Open the Minecraft launcher. Is the Xmx and xms, Xmx means maximum ram and xms means minimum ram, a good ram, if you have, will be Xmx10G Xms 8G. -Xms 堆内存的最小大小，默认为物理内存的1/64. Some explanations:If you have a place where you can put the startup flags in directly, you should be able to just use Aikar's flags there including the xmx and xms values, and leave the max heap size empty wherever else. Explicit Heap Memory – Xms. The uncommitted space is labeled "virtual" in this figure. 一般来讲，大点，程序会启动的快一点，但是也可能会导致机器暂时间变慢。. I suggest leaving it out and replacing it with -Xincgc instead. Activa la optimización del heap de Java. -Xms<heap size>[unit] -Xmx<heap size>[unit] Here, unit denotes the unit in which we’ll initialize the memory (indicated by heap size). Oracle recommends that -Xmn and -Xmx be set to the same value. I want to set up a minecraft vanilla server, I have done this for modded multiple times and I have had this problem multiple times aswell. For client-side Minecraft, it generally makes sense to set the Xmx and Xms to the same value since the working set is largely uniform, for the entire run, and a resize can add extra time to the GC (depends on how the OS exposes this, really). Por ejemplo, a partir de una JVM como la siguiente arrancará con 256 mb de memoria, y permitirá que el proceso use hasta 2048MB de memoria: java -Xmx2048m -Xms256m. com Best values for min-max RAM, Xms & Xmx arguments Edit: Solved, just set them both to the same value! So when running my server (which has 8GB or RAM) I set my Xms to 2G (minimum RAM) and Xmx to 6GB (maximum RAM). Xms should not start at 4GB IIRC XMX is max ram allocated, Xms is the. -xmn2g : Set the young generation. -Xms<var> -Xmx<var> -Xmn<var>. the command that restarts tomcat runs a java process. For the gencon GC policy, you can also use the -Xmo option: If the scavenger is enabled, -Xms ≥ -Xmn + -Xmo. -Xmx Sets the maximum heap size. Oracle recommends that -Xmn and -Xmx be set to the same value. 5. Young generation represents all the objects which have a short life of time. Half the available memory with a minimum of 16 MB and a maximum of 512 MB. It's possible that under Java 8 your application simply needs somewhat more memory. Generally, when moving to G1 from other collectors, particularly the Concurrent Mark Sweep collector, start by removing all options that affect garbage collection, and only set the pause-time goal and overall heap size by using -Xmx and optionally -Xms. Tested on two systems, same result. 为什么一些程序频繁发生GC?有如下原因: l 程序内调用了System. UN/LOCODE 2011-2. Overview In this quick tutorial, we’ll explore the most well-known options that we can use to configure the Java Virtual Machine. บทความวิกิฮาวนี้จะแนะนำวิธีการเพิ่มความจำ (RAM) ที่ Minecraft ใช้ได้ เผื่อจะแก้ memory errors หรือปัญหาความจำไม่พอได้ ถ้าเล่น Minecraft ใน. xmx xms 设置堆内存大小，MC一般不用考虑堆外内存和新老代的问题。建议Xmx设置成最大上限xms设置一个稍小一两G的值，设置成一样的并不会优化性能高负载卡顿还会略微增加。 UnlockExperimentalVMOptions 解锁手动JVM配置，基础选项。The Java Virtual Manager (JVM) requires a certain amount of memory to monitor databases. -Xms will force the JVM to use all the memory available if it is equal to -Xmx, even if it isn't needed (if you do use it it shouldn't be any higher than the normal memory usage; the main benefit is during startup, as otherwise the JVM will resize the heap multiple times, slowing it down). . -Xms: this option sets the initial and minimum Java heap size. -Xmx is the maximum heap size, -Xms is the initial heap size, and the launcher. Password Reset link has expired Forgot Password/ Unlock Account. Best values for min-max RAM, Xms & Xmx arguments Edit: Solved, just set them both to the same value! So when running my server (which has 8GB or RAM) I set. -Xmn is used with -Xgcpolicy:gencon, but can NOT be used with -Xmx or -Xms By default, the launcher will start the game with -Xmx 512M -Xms -128M Which is fine for running vanilla Minecraft, but bad for Modded Minecraft. If -Xmx is passed, the JVM will ignore -XX:MaxRAMPercentage (respectively, if -Xms is passed, the JVM will ignore . Exemplo: java -server -Xms100m -Xmx1500m <outros. Yes. txt and input the memory flags there instead. In this post, we will see about Xms and Xmx parameter in java. , Xmx2048m which means the maximum heap size of JVM will be 2 GB only. Mods, resource packs or view distances above 16 are the only reasons to make it any bigger though. jar My initial java version. 3 Java Version: 1. Consider the following analogy: Imagine you're going to school and you get yourself a single page for taking notes. 5G~2G；64为操作系统对内存无限制。. Nature's Compass - A utility item that allows you to search for any biome's location in the world. 8*10308. como instalar mods en minecraft para celularSkip to main content. 1. 還有10 則留言 收合留言. This is the current start. アプリケーションがうまく動作するために必要なヒープ領域がわかっている場合は、-Xmsと-Xmxを同じ値に設定できます。 そうでない場合は、JVMが初期ヒープ・サイズを使用して開始され、ヒープ使用量とパフォーマンスのバランスが取れるまで、Javaヒープが. Also Java configuration options (command line parameters) can be. บทความเกี่ยวกับ : java -Xms , java -Xmx กำหมด memory ให้ JVM เพื่อป้องกันปัญหา Out of Memory หลายคนคงจะเจอปัญหา out of memory เนื่องจากแรมไม่พอให้ JVM ใช้งาน Sorted by: 77. The options you're looking for are -Xmx and -Xms (this is "initial" heap size, so probably what you're looking for. -Xms and -Xmx simply specifies the range in which the JVM can operate and resize the heap. 通过. Anything after the . JAR via the CMD like this: C:MyFolder>javaw -jarComparing Xmx and Xms. rmi. -Xms and -Xmx Min/Max Allocated Ram to your Minecraft client. -Xmx is the max value of your Java heap size. Xmn. 提供更好的垃圾回收性能 ：将-Xms和. If the value of the -Xms parameter is smaller than the value of the -Xmx. これらを同じ値に設定すると、若い世代のサイズが固定されます(-Xmsと-Xmxを同じ値にすると、合計ヒープ・サイズが固定されるのと同じです)。 これは、 NewRatio で許可されている整数倍よりもきめ細かく若い世代を調整できるので便利です。The size of the space reserved can be specified with the -Xmx option. ex. If -Xms is set to a low RAM allocation, It will start up with that much RAM, no matter the maximum set by -Xmx. To start of with an X number of RAM, use XMS. Maximum heap size is 1/4th of the computer’s physical memory or 1 GB (whichever is smaller) by default. I have a Java microserive that is increasing in memory daily in production that I have just inheritted. Increasing the JVM heap memory using Xmx doesn't work. That invocation typically contains two options: -Xms - which is the minimum memory allocation for java, and. -Xms<size>. Estes parâmetros são passados em linha de comando. Those options set the JVM Heap size directly and it is best to let the JVM infer these based on current limits. 7、-Xloggc:filename：与上面几个配合使用，把相关日志信息记录到文件以便分析。. Aloque mais memória. -Xmx: This option sets the maximum Java heap size. The amount allocated for the Eden generation is the value specified with -Xmn. You can use g if you want to allocate memory in Gigabytes. It is recommended for the two to have the same value, but it isn't required. Do not set -Xmx / -Xms. Java堆大小设置，Xms 和 Xmx设置为老年代存活对象的3-4倍，即FullGC之后的老年代内存占用的3-4倍 永久代 PermSize和MaxPermSize(元空间)设置为老年代存活对象的1. The flag Xmx specifies the maximum memory allocation pool for a Java Virtual Machine (JVM), while Xms specifies the initial memory allocation pool. And the question you linked to was asked long before Java 11 was released, so while it may contain some useful information, this question inherently cannot be a duplicate of that one. If your program need more memory than the value specified in Xms the JVM will take more memory until the limit specified in Xmx. -XX:MetaspaceSize specifies the standard value for full GCs that originate in the Metaspace area. -XX:InitialRAMPercentage is used to calculate initial heap size when InitialHeapSize / -Xms is not set.